U.S. patent application number 10/314009 was filed with the patent office on 2004-06-10 for confined space conditioning system.
This patent application is currently assigned to SPEX INTERNATIONAL. Invention is credited to Sastry, Kal.
Application Number | 20040107711 10/314009 |
Document ID | / |
Family ID | 32468393 |
Filed Date | 2004-06-10 |
United States Patent
Application |
20040107711 |
Kind Code |
A1 |
Sastry, Kal |
June 10, 2004 |
CONFINED SPACE CONDITIONING SYSTEM
Abstract
The present invention is a confined space conditioning system,
which is used to provide conditioning to localized zones of an
enclosure. The confined space conditioning system consists of a
conditioning unit and an enveloped space, enveloping the localized
zone, connected to the conditioning unit. The conditioning unit
uses a low wattage compressor and a heater element to generate
cool, dehumidified air or warm conditioned air to the enveloped
space, as is required by a user of the system. The used conditioned
air is extracted from the enveloped space and is recirculated to
the conditioning unit for reconditioning. The surfaces of the
enveloped space are thermally insulated using thermally insulating
media in order to minimize the cross flow of heat.
Inventors: |
Sastry, Kal; (El Cerrito,
CA) |
Correspondence
Address: |
William L. Botjer
PO Box 478
Center Moriches
NY
11934
US
|
Assignee: |
SPEX INTERNATIONAL
El Cerrito
CA
|
Family ID: |
32468393 |
Appl. No.: |
10/314009 |
Filed: |
December 6, 2002 |
Current U.S.
Class: |
62/176.5 ;
454/188 |
Current CPC
Class: |
Y02B 30/70 20130101;
F24F 2221/125 20130101; F24F 11/77 20180101; F24F 1/022 20130101;
F24F 2003/1446 20130101; F24F 1/04 20130101 |
Class at
Publication: |
062/176.5 ;
454/188 |
International
Class: |
F25D 017/04; F25B
049/00; F24F 009/00 |
Claims
What is claimed is:
1. A confined space conditioning system for conditioning localized
zones of an enclosure, an enclosure being a volume such as a large
room or a container in which only specific localized zones need to
be conditioned, the confined space conditioning system comprising:
a. a conditioning unit; and b. an enveloped space connected to the
conditioning unit whereby the conditioning unit conditions the
enveloped space by supplying conditioned air to the enveloped
space, the conditioned air being air with controlled levels of
temperature and relative humidity.
2. The confined space conditioning system of claim 1 wherein the
conditioning unit comprises: a. a conditioned air generation unit
for generating the conditioned air; b. an air recycling unit for
re-circulating the used air from the enveloped space back to the
conditioned air generation unit for reconditioning; c. a
temperature control unit for controlling the temperature of the
conditioned air generated by the conditioned air generation unit;
and d. a humidity control unit for controlling the relative
humidity of the conditioned air generated by the conditioned air
generation unit; and e. a heat sink unit for disposal of waste heat
generated by the conditioning unit.
3. The confined space conditioning system of claim 2 wherein the
conditioned air generation unit comprises a. a low wattage
refrigerant gas compressor for compressing the refrigerant gas used
in the generation of conditioned air. b. a chiller coil assembly
through which the compressed refrigerant gas is passed; c. a
variable speed blower for blowing the conditioned air to the
enveloped space connected to the conditioning unit.
4. The confined space conditioning system of claim 2 wherein the
conditioned air generation unit further comprises a heater element
for generation of warm conditioned air.
5. The confined space conditioning unit of claim 2 wherein the
conditioning unit further comprises a freshness control unit, which
controls the inlet of fresh air into the enveloped space connected
to the conditioning unit.
6. The confined space conditioning unit of claim 2 wherein the air
recycling unit comprises: a. a suction means for extracting the
used conditioned air from the enveloped space connected to the
conditioning unit; and b. a connecting duct for passing the
extracted air to the conditioned air generation unit for
re-conditioning; and c. an operating damper unit for allowing a
part of the recycled air to bypass the chiller coil assembly and
mix with the chilled air that passes over the chiller coil assembly
in order to control the humidity of the conditioned air.
7. The confined space conditioning system of claim 1 wherein the
enveloped space comprises: a. a set of thermal insulation media,
the thermal insulation medium being a layer or layers of insulation
material covering the volume of the enveloped space for minimizing
the cross flow of heat across the enveloped space; b. a sealing
apparatus for securing the free ends of the thermal insulation
media; c. an inlet duct for allowing the inflow of conditioned air
from the conditioning unit into the enveloped space; and d. an
outlet duct for allowing the outflow of used air from the enveloped
space to the conditioning unit.
8. The confined space conditioning system of claim 7 wherein the
sealing apparatus secures the free ends of the thermal insulation
media for minimizing air leakage from the enveloped space.
9. A confined space conditioning system for conditioning localized
zones of a large enclosure, the confined space conditioning system
comprising: a. a conditioning unit; b. an enveloped space connected
to the conditioning unit wherein the conditioning unit comprises:
i. a conditioned air generation unit for generating conditioned
air, the conditioned air being air with controlled/desirable levels
of temperature and relative humidity; ii. an air recycling unit for
recycling the used air from the enveloped space back to the
conditioned air generation unit for conditioning; iii. a
temperature control unit for controlling the temperature of the
conditioned air generated by the conditioned air generation unit;
and iv. a humidity control unit for controlling the humidity
conditions of the conditioned air generated by the conditioned air
generation unit; and the enveloped space comprises: i. a set of
thermal insulation media, the thermal insulation medium being a
layer or layers of insulation material covering the volume of the
enveloped space for minimizing the outflow of heat from or into the
enveloped space; ii. a sealing apparatus for sealing the free ends
of the thermal insulation media; iii. an inlet duct for allowing
the inflow of conditioned air from the conditioning unit into the
enveloped space; and iv. an outlet duct for allowing the outflow of
used air from the enveloped space to the conditioning unit.
Description
BACKGROUND
[0001] The present invention relates to air conditioning, heating
and ventilation. More specifically, the present invention relates
to a system for conditioning a given localized space.
[0002] Air conditioning systems maintain suitable temperature and
humidity conditions in enclosed spaces. This is achieved by
supplying conditioned air to these enclosed spaces. Conditioned air
may include cooled air, dehumidified air or warmed air, as the case
may be, and the enclosure could be a large room connected to a
window air conditioner or a central air conditioner (wherein the
air conditioner "conditions" the entire room).
[0003] Apart from providing personal air conditioning, such systems
are also used in diverse fields like commercial, research, medical
and industrial applications. These air conditioning systems, by
virtue of their design, cannot be used to provide only localized
conditioning to specific zones of the enclosure and hence are not
suitable for use in situations where only localized conditioning is
required.
[0004] A common disadvantage of the existing air conditioning
systems is that they involve high initial equipment cost and
continuous use of large amounts of energy. (Since the systems are
essentially designed to condition complete enclosures, they need to
be high capacity systems, which in turn increases the equipment
cost associated with these systems.) However, there exist several
situations in everyday life where only specific zones of an
enclosure need to be conditioned. For example, in a large dining
hall, conditioning may not be required for the complete hall; in
fact, it may be required only around the dining table.
Nevertheless, even in these situations, current air-conditioning
systems would end up conditioning the complete hall, and hence
require high equipment and energy costs.
[0005] Another example is a commercial office space where it may be
desirable to condition space around a copying machine (in order to
prevent the sticking of papers due to high humidity). In such a
situation, there is no need to condition the entire copying room.
Yet another example is an industrial application where a control
and switch panel has to be kept in a controlled atmosphere (and not
the entire control room). In all these situations, a user can save
a significant amount of resources if he provides localized
conditioning only around the copying machine or the control and
switch panel.
[0006] Due to the above-mentioned limitations of the existing air
conditioning systems, these systems cannot address the requirements
of localized conditioning. There have been attempts at designing
systems that can be used to provide conditioning to a localized
region.
[0007] U.S. Pat. No. 6,446,455 describes one such conditioning
system; this makes use of the concept of spot cooling. Although
such systems improve the localized conditioning effect in a
specific region, they still consumes large amount of energy (than
is required to condition just the localized zone). This is because
such systems also end up conditioning the air that surrounds the
localized zone.
[0008] U.S. Pat. No. 6,171,333 describes another system for
localized conditioning. The system described in this patent
describes a comforting unit. The comforting unit comprises a
bladder, which consists of flexible panels coupled together to
encompass an air space there between them. The air space is heated
or cooled in order to provide heating or cooling comfort to the
user. However, this invention does not involve direct heating or
cooling. The invention provides heating or cooling comfort to the
user indirectly by heating or cooling an air space that is not in
direct contact with the user.
[0009] U.S. Pat. No. 5,989,285 describes another such system for
providing indirect localized conditioning. The invention described
in this patent comprises a temperature controlled blanket and
bedding wherein a temperature controlled fluid is circulated
through the blanket in order to maintain the blanket at a specific
temperature. A limitation of this conditioning system is that it
provides heating or cooling comfort to a user only in an indirect
manner (i.e., by heating or cooling an air space, which is not in
contact with the user) and does not directly condition the enclosed
space in the same manner as typical air conditioning systems.
[0010] U.S. Pat. No. 6,453,678 describes a direct current mini air
conditioning system that enables conditioning of small enclosed
spaces (such as cabins of trucks and boats). However, the use of
the mini air conditioning system described in this patent is
restricted to conditioning the entire enclosed space, and it does
not encompass conditioning of localized zones within the space.
Further, the system described in this patent uses a direct current
air conditioner, which cannot be used in normal household or
commercial conditions where direct current (i.e., DC current)
sources are not available.
[0011] Hence, there exists a need for a conditioning system that is
relatively less expensive, that can be powered by alternating
current (i.e., AC current) sources, and that can provide localized
conditioning to specific zones of a confined space in an
energy-efficient manner.
SUMMARY
[0012] It is a general object of the invention to provide a system
for air conditioning, heating and ventilation.
[0013] It is an object of the invention to provide a confined space
conditioning system that allows for controlled airflow, temperature
and humidity conditions within a zone in an enclosure.
[0014] Yet another object of the invention is to provide a low
energy consumption conditioning system for conditioning specific
localized zones within an enclosure at a low initial cost.
[0015] In the preferred embodiment, the invention is directed to a
confined space conditioning system that conditions localized zones
of a given enclosure. The confined space conditioning system
comprises of a conditioning unit connected to an enveloped space.
The conditioning unit supplies conditioned air to the enveloped
space in order to maintain controlled levels of temperature and
relative humidity in the enveloped space.
[0016] The conditioned air within the enveloped space is circulated
back to the conditioning unit. Due to the re-circulation of this
"used air," lesser amount of energy is required (as compared to
energy required for conditioning the entire enclosed space). The
surfaces of the enveloped space are covered by a layer or layers of
thermal insulation media. This thermal insulation reduces heat
losses from the exposed surface area as well as leakage of
conditioned air from the enveloped space.
[0017] In another embodiment, the present invention provides a
system, which is designed such that only a desired enveloped space
is cooled or heated to a level suitable for the individual or
individuals or other entities occupying the enveloped space.
[0018] An advantage of the present invention is that it provides a
conditioning system that has lower connected wattage and energy
consumption as compared to the standard central, window or split
air conditioners.
[0019] Another advantage of the present invention is that the
enveloped space is of much smaller volume than the total enclosure,
and this allows for quick conditioning of the enveloped space.
[0020] Another advantage is that the exposed external surface area
of the enveloped space is much smaller than the exposed surface
area of the total enclosure, and this results in reduced cross-flow
of heat across the exposed surface area of the enveloped space.
[0021] Another advantage of the invention is that it provides a
compact and lightweight conditioning system as compared to split or
window air conditioners.
[0022] Another advantage of the invention is that it provides a
conditioning system that produces lesser noise than standard window
air conditioners and air coolers.
[0023] Another advantage of the invention is that it provides a
conditioning system that does not require a ceiling fan to attain
the comfort levels of temperature.
[0024] Yet another advantage of the invention lies in the ease of
installation of the conditioning system.
[0025] Yet another advantage of the invention is that it provides a
conditioning system with features of easy mobility and
cartability.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The preferred embodiments of the invention will hereinafter
be described in conjunction with the appended drawings provided to
illustrate and not to limit the invention, wherein like
designations denote like elements, and in which:
[0027] FIG. 1 is a representation of the general environment in
which the present invention works;
[0028] FIG. 2 is a schematic representation showing the connection
of conditioning unit 102 to enclosure 106 of FIG. 1 in further
detail in accordance with the present invention;
[0029] FIG. 3 is a diagram showing conditioning unit 102 and its
various components; and
[0030] FIG. 4 is an illustration showing the conditioning unit
connected to an enveloped bed in accordance with a preferred
embodiment of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0031] The present invention provides a confined space conditioning
system for conditioning localized zones of an enclosure. The
enclosure refers to a volume, within which only specific localized
zones need to be conditioned.
[0032] FIG. 1 is a representation of the general environment in
which the present invention works. The present invention comprises
a conditioning unit 102 located in an enclosure 104 and connected
to an enveloped space 106, which is built inside the enclosure.
Conditioning unit 102 generates conditioned air that is supplied to
enveloped space 106. Conditioned air may include cooled air,
dehumidified air or warmed air (as required). Enveloped space 106
can be designed around any structure like a dining table, bed,
copying machine or other equipment, or it may simply be designed
around an empty space in enclosure 104. One or more of humans,
animals, plants, or commercial equipment, research apparatus,
industrial units or other entities may occupy enveloped space
106.
[0033] The surfaces of enveloped space 106 are covered by thermal
insulation media in order to minimize the cross flow of heat
through the surfaces of the enveloped space. The thermal insulation
medium can be a layer or layers of insulation material used to
cover the surfaces of the enveloped space.
[0034] The thermal insulation medium can be in the form of a
curtain, wall covering or any other suitable form and can be made
of a thermal insulating material like plastic, cotton, synthetic
fabrics, their blends or other materials having suitable thermal
insulating properties and permeability. The design of the thermal
insulation medium is such that it allows adequate permeability for
automatic purging of gases like carbon dioxide and water vapor from
the enveloped space as well as corresponding intake of fresh air
into the enveloped space (for maintaining freshness). The free ends
of the thermal insulation media are sealed using an appropriate
sealing apparatus. The sealing apparatus is used to secure the free
ends of the thermal insulation media with other structures in the
enveloped space in order to minimize the leakage of conditioned air
from the enveloped space.
[0035] FIG. 2 is a schematic representation showing the connection
of conditioning unit 102 to enclosure 106 of FIG. 1 in further
detail in accordance with the present invention. Enveloped space
106 is connected to a delivery duct 202 and a connecting duct 204
of conditioning unit 102. Conditioning unit 102 generates
conditioned air, which is supplied to enveloped space 106 through
delivery duct 202. The conditioned air-conditions the environment
inside enveloped space 106 and the used conditioned air is supplied
back to conditioning unit 102 through connecting duct 204.
Conditioning unit 102 reconditions the used conditioned air and
supplies it back to enveloped space 106 through delivery duct
202.
[0036] FIG. 3 is a diagram showing conditioning unit 102 and its
various components. Conditioning unit 102 generates conditioned air
using air from the enveloped space. The used conditioned air from
the enveloped space is reconditioned by circulating it back to the
conditioning unit. For this purpose, conditioning unit 102 has a
suction unit 302 for extracting the used conditioned air from the
enveloped space. The suction unit consists of a wire mesh and a
suction blower through which the used conditioned air is sucked
from the enveloped space. Conditioning unit 102 has connecting duct
204 for directing the extracted used conditioned air for
re-conditioning. Conditioning unit 102 further consists of delivery
duct 202 for delivering the conditioned air to the enveloped space.
Delivery duct 202 has a distribution grill 304 at its outlet
through which the conditioned air is delivered to the enveloped
space. The distribution grill 304 is provided with louvers to
control the volume and direction of conditioned air to be delivered
to the enclosure 106. Conditioning unit 102 also has a set of
adjustable legs 306 for adjusting its height.
[0037] Conditioning unit 102 works on vapor compression
refrigeration cycle. A low wattage refrigerant gas compressor 306
compresses the refrigerant gas, which after compression is passed
through a condenser coil assembly 308. Refrigerant gas compressor
306 can be a rotary or reciprocating compressor with lower wattage
than the compressors used in conventional air conditioning systems.
Due to the lower wattage, refrigerant gas compressor 306 has lower
energy requirements as compared to the compressors used in
conventional air conditioning systems. Condenser coil assembly 308
condenses the compressed refrigerant gas coming from refrigerant
gas compressor 306. A condenser fan 310 draws ambient air from the
surrounding space over condenser coil assembly 308 in order to
condense the refrigerant gas passing though condenser coil assembly
308 into a liquid. The air drawn by condenser fan 310 over the
condenser coil assembly 308 becomes hot containing waste heat and
is passed over a heat sink unit 324 to properly dispose the hot
air.
[0038] The condensed refrigerant liquid from condenser coil
assembly 308 is allowed to flash at a lower pressure by passing it
through an expansion device. The expansion device can be a
capillary tube or a valve, which allow the flashing of the
condensed refrigerant liquid as it passes through the capillary or
the valve. The expanded refrigerant vapor then passes through a
chiller coil assembly 312. The refrigerant vapor passing through
chiller coil assembly 312 extracts the heat energy from contact air
that passes over chiller coils of chiller coil assembly 312. The
low pressure refrigerant gas from the chiller coil assembly 312 is
drawn by refrigerant gas compressor 306. A collection tray 314 is
used to collect water that condenses over chiller coil assembly
312. A condensate drain pipe 316 is used to drain the condensate
from chiller coil assembly 312 to collection tray 314.
[0039] In case conditioning unit 102 is required to generate warm
conditioned air, a heater element 318 is activated and air is
conditioned by passing it over the activated heater element
318.
[0040] Conditioning unit 102 further consists of a temperature
control unit for controlling the temperature of the conditioned air
being supplied to the enveloped space. The temperature control unit
receives the desired temperature value as input from the user
through a user interface and controls the functioning of heater
element 318 or refrigerant gas compressor 306 in order to maintain
the temperature of the conditioned air. The temperature control
unit comprises a thermostat and associated circuitry for measuring
the temperature inside the enveloped space and uses the measured
temperature value to control the functioning of refrigerant gas
compressor 306 or heater element 318. Conditioning unit 102 also
has a humidity control unit, which receives the desired humidity
conditions as input through a user interface and uses this input to
control relative humidity of the conditioned air. The humidity
control unit comprises an operating damper unit 320 and associated
devices for controlling relative humidity of the conditioned air.
Operating damper unit 320 splits the higher humidity recycled air
into two parts and blends it with the lower humidity chilled air
coming from the chiller coils. The mixing of the high humidity air
and the lower humidity air is used to achieve the desired humidity
level of the conditioned air. By varying the ratio in which the
high humidity air is split for mixing with the lower humidity
chilled air, the humidity levels of the conditioned air can be
varied. A variable speed air blower 322 is used to blow the
conditioned air through delivery duct 202 into the enveloped space.
Conditioning unit 102 further consists of a freshness control unit,
which allows fresh air into the enveloped space at a known rate in
order to maintain freshness in the enveloped space.
[0041] The conditioning unit 102 is provided with lockable castors
326 to enable cartability and portability of the unit 102.
[0042] FIG. 4 is an illustration showing the conditioning unit
connected to an enveloped bed in accordance with a preferred
embodiment of the present invention. Conditioning unit 102 is
connected to enveloped space 402, which in this case, has been
designed around a bed 404. Conditioning unit 102 has the option of
supplying warm air or cool, dehumidified air, as desired to
enveloped space 402. Conditioning unit 102 also has the provision
of re-circulating the used conditioned air from the enveloped space
back to conditioning unit 102 for reconditioning. The used
conditioned air is extracted from the enveloped space,
reconditioned and supplied back to enveloped room 402. Fresh air
enters the enveloped space through small air gaps that are custom
designed or that naturally exist in the thermal insulation
media.
[0043] Conditioning unit 102 uses a low wattage refrigerant gas
compressor for cooling the air and a heater element for heating the
air. The selection of having cooled air, dehumidified air or warmed
air is done through a selection device provided inside the
enveloped space. The selection device can be a switch present on
conditioning unit 302 or a remote control device. The conditioning
effect is localized only to the enveloped space designed around the
bed. Depending upon the size of the enclosed "room," the zone
outside the enveloped space may get warmer due to heat rejection
from the air conditioner; in such a case, an exhaust hose or an
exhaust fan can be fitted on one of its sidewall or a window (to
remove the heat from the enclosure).
[0044] The conditioning unit is capable of working under hot, humid
and cold climates. The conditioning system can be powered using a
common household single-phase low amperage circuit.
[0045] Enveloped space 402 may be created on a bed by covering its
four sides with a thermal insulation medium. In the embodiment
shown in FIG. 4, the thermal insulating medium is in the form of
hanging curtains made of a 100% Polyester fabric and having a mass
density of 105 gram per square meter.
[0046] Bed 404 can have typical king-size, queen-size or other
dimensions suitable for intended applications of sleeping or
resting. The free ends of the thermal insulation medium are secured
by gravity sealing, hanging curtains (with edges on the side of the
bed to minimize any leakage of conditioned air). Sealing the free
ends of the enveloping curtains minimizes air leakage and
introduces built-in flexibility, and this protects the system from
any damage due to accidental stretch or pull etc. Conditioned air
from conditioning unit 102 is allowed inside enveloped space 402
near the head, foot, left or the right side of the bed and the used
conditioned air is allowed to exit from the opposite end.
[0047] A person skilled in the art can see that the illustration
provided in the above-cited embodiment is just one example of
creating an enveloped space. The enveloped space can be created
around any structure and can be of any size and shape. For example,
the enveloped space as described in the above-cited illustration
can be built around a child bassinette, a dining table, an
individual working at a personal computer, a laboratory instrument,
a photocopying machine or other structures. Further, the
conditioned air can be allowed to enter and the used conditioned
air, which is subsequently reconditioned, can be allowed to exit
from any side of the enveloped space.
[0048] The confined space conditioning system offers an efficient
solution to meet the needs of localized space conditioning. The
enveloped space has a lower surface area than the enclosure within
which it has been built; as a result, the energy losses from the
smaller surface area of the envelope material are much smaller
(than the losses, which would result from a larger surface area of
the enclosure). Hence, this system is highly efficient from an
energy consumption perspective.
[0049] The confined space conditioning system further allows for
quick conditioning of the enveloped space because of the smaller
volume of the enveloped space as compared to the enclosure (and
lower thermal mass of the envelope material as compared with the
higher thermal mass of the enclosure).
[0050] In an alternative embodiment, the enveloped space can be
provided with added features like a smoke detector, fire retardant
properties of the thermal insulation medium, air freshener, reading
lamp, music system, telephone connection and shelf space.
[0051] In another alternative embodiment, a health filter or an ion
generator can be included in the conditioning unit to remove
irritants and allergens from the air stream.
[0052] In yet another alternative embodiment, the system can be
used to provide inert conditioning to an enveloped space by the use
of an inert gas like Nitrogen instead of air. Such an embodiment
may be used for research purposes where inert conditioned
environments are required.
[0053] In yet another embodiment, the conditioning unit and the
enveloped space can be integrated into one single unit. Such an
embodiment can be custom designed for the purpose of intended end
use.
[0054] In another alternative embodiment, the conditioning system
itself can be split into compressor-condensing subsystem and
chiller subsystem, and subsequently, the chiller subsystem can be
integrated with the enveloped space.
[0055] While the preferred embodiments of the present invention
have been illustrated and described, it will be clear that the
present invention is not limited to these embodiments only.
Numerous modifications, changes, variations, substitutions and
equivalents will be apparent to those skilled in the art without
departing from the spirit and scope of the present invention as
described in the claims.
* * * * *