TITLE
OUTDOOR UNIT OF AN AIR CONDITIONING SYSTEM
FIELD OF THE INVENTION
The present invention relates to an air conditioning system. More particularly the present
invention is directed to construction of an outdoor unit of an air conditioning system.
BACKGROUND
Air conditioning (often referred to as AC) is the process of altering the properties of air (e.g.
temperature and humidity) to more favorable conditions, thus providing a stream of air at a
desired temperature. Air conditioners use refrigeration to cool indoor environment, taking
advantage of a remarkable physical law: When a liquid converts to a gas (in a process called
phase conversion), it absorbs heat and when a gas converts into liquid it gives off heat. Air
conditioners exploit this feature of phase conversion by forcing special chemical compounds
called refrigerants to evaporate and condense over and over again in a closed system of coils.
When hot air flows over the cold, low-pressure evaporator coils, the refrigerant inside absorbs
heat as it changes from a liquid to a gaseous state. To keep cooling efficiently, the air conditioner
has to convert the refrigerant gas back to a liquid again. To do that, a compressor puts the gas
under high pressure, producing unwanted heat. All the extra heat created by compressing the gas
is then evacuated to the outdoors with the help of coils called condenser coils, and a fan. As the
gas cools, it changes back to a liquid, and the process starts all over again.
Compressors generate heat while compressing the gas under pressure. Heat of compression,
thermal losses from motor windings and frictional heat gain at load bearing surface are the main
sources of heat. All compressors are designed to tolerate such normal thermal gains. Although
compressors are designed to handle normal thermal temperature gains however, when they are
operated outside the designed parameters and especially at very high ambient temperatures, they
may be potentially damaged or their life expectancy may reduce. As the temperature and
pressure inside the compressor chamber builds up continuously due to overheating in absence of
proper ventilation mechanism, the compressor may trip off frequently. Many a times the service
3
technicians have to charge the refrigerant in the air conditioner at customer end. In case the
refrigerant gets overcharged, it may result in flooding. Flooding is the continuous return of liquid
refrigerant to the compressor where it mixes with lubrication oil, while the system is operating.
Since the liquid refrigerant along with the lubrication oil is non-compressible it exerts heavy
hydraulic pressure on the compressor components thereby resulting in component failures. Also,
while operating at such high ambient temperature and pressure, a large amount of power is
consumed by the compressor.
Therefore, there is an immense need felt in the field of air conditioning systems to reduce the
temperature and pressure of the compressor and avoid severe issues as discussed above. In case,
had there been a proper ventilation mechanism in the compressor chamber, the temperature of
the compressor could be lowered and the compressor could work at high ambient temperatures or
in conditions where the compressor gains very high temperature due to overloading. This will
also result in saving power.
This invention therefore provides a suitable mechanism for reducing the temperature of the
compressor in an air conditioning system.
OBJECT OF THE INVENTION
The object of the present invention is to provide a suitable mechanism for reducing the
temperature of the compressor in an air conditioning unit thus addressing problems as described
in the prior art.
SUMMARY
The present invention provides suitable mechanism for reducing excessive temperature of a
compressor in an outdoor unit of an air conditioning system. More particularly, the present
invention provides a mechanism for forced circulation of air inside the compressor chamber. The
compressor chamber of an air conditioner comprises of a compressor and is sealed from all sides.
In order to have a forced air circulation in the compressor chamber, an exhaust fan is installed on
one of the walls of the compressor chamber. Further, louvers are provided on another wall of the
compressor chamber. The louvers allow the ambient air present outside the compressor chamber
4
to mix with the hot air in the compressor chamber and the exhaust fan allows the hot air of the
compressor chamber to evacuate to the outdoors.
Accordingly, the present invention relates to an outdoor unit of an air conditioner, comprising a
container shaped body defined by a front panel, a back panel, a top panel, a bottom panel and
two side panels, said container shaped body partitioned into two sections by a partitioning wall
forming a compressor chamber and a condenser chamber; the condenser chamber comprising of
condenser coils and a fan for blowing air for exchanging heat with a refrigerant in the condenser
coils; and the compressor chamber housing a compressor for compressing the refrigerant and is
sealed from the condenser chamber, said compressor chamber is provided with ventilation means
to allow exchange of outdoor air.
According to another aspect of the present invention, the outdoor unit of an air conditioner is
provided with ventilation means which comprise of louvers on the back panel and the front
panel, said one louver located in front of the compressor and the other louver located near the
edge of the top panel.
According to yet another aspect of the present invention, the outdoor unit of an air conditioner is
described, wherein the ventilation means comprises of an exhaust fan on either of the front panel,
the side panel or the back panel.
According to still another aspect of the present invention, the outdoor unit of an air conditioner is
described, wherein the ventilation means comprises of a louver and an exhaust fan on either of
the back panel or the front panel or the side panel.
According to another aspect of the present invention, the outdoor unit of an air conditioner is
described, wherein the louver is located in front of the compressor and the exhaust fan is located
near the edge of the top panel.
According to yet another aspect of the present invention, the outdoor unit of an air conditioner is
described, wherein the ventilation means comprises of a fan for blowing outside air on to the
compressor and a louver, said fan located on either of the back panel, front panel or the side
panel.
5
According to still another aspect of the present invention, the outdoor unit of an air conditioner is
described, wherein the louver comprise of plurality of slats which are inclined upwards or
downwards or are straight or are in a combination of upward, downward or straight.
According to another aspect of the present invention, the outdoor unit of an air conditioner is
described, wherein the ventilation means comprises of a louver and an exhaust fan on the
partition wall separating the compressor chamber and the condenser chamber.
According to yet another aspect of the present invention, the outdoor unit of an air conditioner is
described, wherein the air conditioner can perform within ambient temperature of 20˚C to 55 ˚C
and 195V to 253V.
According to still another aspect of the present invention, the outdoor unit of an air conditioner is
described, wherein the exhaust fan starts functioning as soon as compressor starts running.
According to another aspect of the present invention, the outdoor unit of an air conditioner is
described, wherein the exhaust fan is provided with a mesh in its front that is in contact with the
ambient atmosphere.
BREIF DESCRIPTION OF DRAWINGS
Further aspects and advantages of the present invention will be readily understood from the
following detailed description with reference to the accompanying drawings. Reference numerals
have been used to refer to identical or functionally similar elements. The figures together with a
detailed description below, are incorporated in and form part of the specification, and serve to
further illustrate the embodiments and explain various principles and advantages, in accordance
with the present invention wherein:
Fig. 1 illustrates an outdoor unit of an air conditioning system.
Fig. 2a and Fig. 2b illustrates two perspective views of the outdoor unit of an air conditioner.
Fig. 3a and Fig. 3b illustrates the outdoor unit of an air conditioning system in accordance with
one embodiment of the present invention.
Fig. 4 illustrates the outdoor unit of an air conditioning system in accordance with one
embodiment of the present invention.
6
Fig. 5 illustrates an exploded view of the outdoor unit of an air conditioning system in
accordance with one embodiment of the present invention.
Fig. 6 illustrates various embodiments of louvers considered for the present invention.
Fig. 7 illustrates another embodiment of the present invention for forcing ambient air flow inside
the compressor chamber.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, there is shown an illustrative embodiment of the invention
compressor chamber of an air conditioner. It should be understood that the invention is
susceptible to various modifications and alternative forms; specific embodiment thereof has been
shown by way of example in the drawings and will be described in detail below. It will be
appreciated as the description proceeds that the invention may be realized in different
embodiments.
Before describing in detail embodiments it may be observed that the novelty and inventive step
that are in accordance with the present invention reside in the construction of the compressor
chamber, accordingly, the drawings are showing only those specific details that are pertinent to
understanding the embodiments of the present invention so as not to obscure the disclosure with
details that will be readily apparent to those of ordinary skill in the art having benefit of the
description herein.
The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a
non-exclusive inclusion, such that a setup, device that comprises a list of components does not
include only those components but may include other components not expressly listed or
inherent to such setup or device. In other words, one or more elements in a system or apparatus
proceeded by “comprises… a” does not, without more constraints, preclude the existence of
other elements or additional elements in the system or apparatus. A compressor in an air
conditioning system with suitable mechanism to reduce excessive temperature and pressure will
now be described in detail with reference to the accompanying drawings.
7
Fig. 1 illustrates an outdoor unit (100) of an air conditioning system. The outdoor unit has a
cuboidal structure and is divided into two sections. One section houses the compressor for
compressing the refrigerant and other section comprises of the condenser coils and a fan for
blowing air for exchanging heat with the refrigerant in the condenser coils. These sections are
referred to as compressor chamber (101) and condenser chamber (102) in the description. The
outdoor unit further has a front panel, a back panel, a bottom, a top panel and two side panels.
Fig. 2a and Fig. 2b illustrates two perspective views of the outdoor unit of an air conditioner.
Fig. 2a illustrates front panel (201), top panel (202) and a side panel (203). Figure 2b illustrates
back panel (204) and the other side panel (205).
Fig. 3a and Fig. 3b illustrates the outdoor unit of an air conditioning system in accordance with
one embodiment of the present invention. The outdoor unit comprises a front and a back panel, a
bottom and a top panel and two side panels. These six panels are connected together to form a
partially closed unit or a container shaped body. The said outdoor unit (300) is divided into two
sections forming a condenser chamber (301) and a compressor chamber (302). The condenser
chamber (301) comprises of a condenser coils and a fan (303) for blowing air for exchanging
heat with the refrigerant in the condenser coils. The compressor chamber (302) comprises of a
compressor which compresses the gas under pressure. The compressor chamber (302) is
separated from the condenser chamber (301) by a partitioning wall.
In accordance with one embodiment of the present invention, the compressor chamber (302) is
provided with louvers (307) at the back panel. These louvers (307) are located near the bottom
panel such that they are adjacent to the compressor which rests on the inside surface of the
bottom panel. The compressor chamber (302) is further provided with an exhaust fan (305) in the
front panel. In accordance with one embodiment of the present invention, the exhaust fan (305)
starts functioning simultaneously with the compressor. The exhaust fan (305) is located near to
top panel in the front panel. Such construction of the compressor chamber (302) allows flow of
ambient air from the outside environment into the compressor chamber (302). The same is
illustrated with the help of arrows in figure 4. The ambient air which is at a lower temperature
enters the compressor chamber (401) from the louvers (402) and passes around the compressor
8
(403) and gets heated up. This heated air rises upwards towards the top panel and is evacuated by
the exhaust fan (404). In this way there is a continuous supply of ambient air in the compressor
chamber (401), thus leading to fall in temperature of the compressor chamber (401) and thereby
the compressor (403). Such construction of the compressor chamber will lead to fall in
temperature of compressor by up to 6°C. The present invention, thus also leads to improvement
in cooling capacity and reduction in the total power consumption by the air conditioning system.
The same is further illustrated with the help of the comparison table below. The table provides a
comparison between the air conditioner of the present invention vis-à-vis the conventionally
known air conditioners. ID temperature is the temperature required at the indoor unit and the OD
temperature is the ambient air temperature around the outdoor unit. DBT and WBT signify the
dry bulb temperature and wet bulb temperature.
ID Temp
Deg C
OD Temp
Deg C Parameter Present
Invention
Conventional
AC
%age of
improvement
DBT/WBT
27/19
DBT/WBT
35/24 @
230 V
Ambient Air In Temp 35 NA
Hot Air Out Temp 40.80 NA
Compressor Body
Temp 77 80
Cooling Capacity 5290 5270 0.38%
Power 1630 1640 0.61%
EER 3.25 3.21 1.00%
DBT/WBT
52/30
@230 V
Ambient Air In Temp 52 NA
Hot Air Out Temp 57 NA
Compressor Body
Temp 78 82
Cooling Capacity 4910 4706 4.32%
Power 2193 2231 1.69%
EER 2.24 2.11 6.09%
DBT/WBT
55/31 @
195 V
Ambient Air In Temp 55 NA
Hot Air Out Temp 60 NA
Compressor Body
Temp 80 85
Cooling Capacity 4383 Not Working
Power 2344 Not Working
EER 1.87 Not Working
9
The ID temperature is kept constant at 27/19˚C whereas the OD temperature and the voltage are
varied. At OD temperature of 35/24˚C and at 230V, the present invention helps to exhaust the
hot air from the compressor chamber which results in drop in temperature of compressor
chamber by about 3 ~ 5˚C. This reduces the compressor body temperature by up to 4˚C, thus
resulting in better cooling capacity, less power consumption and improving the overall
performance of the product by 1%.
At OD temperature of 52/30˚C and at 230V, the present invention helps to exhaust the hot air
from the compressor chamber which results in drop in temperature of compressor chamber by
about 3 ~ 5˚C. This reduces the compressor body temperature by up to 4˚C, thus resulting in
better cooling capacity, less power consumption and improving the overall performance of the
product by about 4 ~ 6%.
At OD temperature of 55/31˚C and at 195V, the conventional air conditioners may not work and
trip. However, the present invention works without any issue.
Fig. 5 illustrates an exploded view of the outdoor unit of an air conditioning system in
accordance with one embodiment of the present invention. The outdoor unit (500) has a cuboidal
structure and is divided into two sections with the help of a partitioning wall (505). One section
houses the compressor (510) for compressing the refrigerant and other section comprises of the
condenser coils (511) and a fan (507) for blowing air for exchanging heat with the refrigerant in
the condenser coils (511). These sections are referred to as compressor chamber and condenser
chamber. The outdoor unit further has a front panel (504), a back panel (511), a bottom (502), a
top panel (501) and two side panels (503). Further a mesh (506) is provided in front of the
condenser fan. Ventilation means are provided in the outdoor unit which helps in circulation of
outdoor or ambient air inside the compressor chamber. The ventilation means may comprise of at
least one louver or an exhaust fan (509) or a combination of both. The louvers or the fan may be
provided on any of the walls i.e. side panel, front panel, back panel, top or bottom panel or the
partition wall (505) partitioning the compressor chamber from the condenser chamber of the
compressor chamber. The exhaust fan (509) may be covered and protected from dust and other
particles by providing a mesh (508) in its face that is exposed to the atmosphere.
10
Fig. 6 illustrates the various designs of louvers provided at back panel of the compressor
chamber. In figure 6a, the louvers are designed such that they are straight or in other words they
are aligned perpendicular to the back panel of the compressor chamber. In figure 6b all the
louvers are designed such that they are inclined upwards. In figure 6c all the louvers are designed
such that they are inclined downwards. The figure 6d illustrates half louvers inclined upwards
and half louvers inclined downwards. In figure 6e, which is the preferential embodiment of the
present invention, the louvers are designed such that few upper louvers are inclined upwards; the
louvers at the middle are aligned straight as in figure 6a; and the remaining louvers at the bottom
are inclined downwards.
It may be observed that the exhaust fan with varying diameter and having motor of different rpm
may be used for implementing this invention. Also, instead of louvers, one may provide a mesh
kind of opening to allow the ambient air inside the compressor chamber.
Fig. 7 illustrates another embodiment of the outdoor unit (700) of an air conditioner. In the said
embodiment the air flow is forced inside the compressor chamber with the help of a fan (701).
As shown, the fan is mounted in front of the compressor in the front panel or in the back panel. A
window having louvers for ventilation is provided at the side panel of the compressor chamber.
The fan throws the ambient air on the compressor and the window at the side panel helps the air
to escape to the outer atmosphere.
Thus, it is possible by the way of this invention to reduce the temperature of compressor by
having a mechanism for forcing circulation of ambient air inside the compressor chamber.
Further, with the reduction in temperature of compressor, there is an improvement in cooling
capacity and reduction in power consumption by the air conditioner.
While the invention has been described with reference to a preferred embodiment, it is apparent
that variations and modifications will occur without departing the theme of the invention. It is
therefore contemplated that the present invention covers any and all modifications, variations or
11
equivalents that fall within the scope of the basic underlying principles disclosed above and
claimed therein.
12
We Claim:
1. An outdoor unit of an air conditioner, comprising:
a container shaped body defined by a front panel, a back panel, a top panel, a bottom
panel and two side panels, said container shaped body partitioned into two sections by a
partitioning wall forming a compressor chamber and a condenser chamber;
the condenser chamber comprising of condenser coils and a fan for blowing air for
exchanging heat with a refrigerant in the condenser coils; and
the compressor chamber housing a compressor for compressing the refrigerant and is
sealed from the condenser chamber, said compressor chamber is provided with
ventilation means to allow exchange of outdoor air.
2. The outdoor unit of an air conditioner as claimed in claim 1, wherein the ventilation
means comprises of louvers on the back panel and the front panel, said one louver located
in front of the compressor and the other louver located near the edge of the top panel.
3. The outdoor unit of an air conditioner as claimed in claim 1, wherein the ventilation
means comprises of an exhaust fan on either of the front panel, the side panel or the back
panel.
4. The outdoor unit of an air conditioner as claimed in claim 1, wherein the ventilation
means comprises of a louver and an exhaust fan on either of the back panel or the front
panel or the side panel.
5. The outdoor unit of an air conditioner as claimed in claim 4, wherein the louver is located
in front of the compressor and the exhaust fan is located near the edge of the top panel.
6. The outdoor unit of an air conditioner as claimed in claim 1, wherein the ventilation
means comprises of a fan for blowing outside air on to the compressor and a louver, said
fan located on either of the back panel, front panel or the side panel.
13
7. The outdoor unit of an air conditioner as claimed in any of the above claims, wherein the
louver comprise of plurality of slats which are inclined upwards or downwards or are
straight or are a in a combination of upward, downward or straight.
8. The outdoor unit of an air conditioner as claimed in claim 1, wherein the ventilation
means comprises of a louver and an exhaust fan on the partition wall separating the
compressor chamber and the condenser chamber.
9. The outdoor unit of an air conditioner as claimed in claim 1, wherein the air conditioner
can perform within ambient temperature of 20˚C to 55 ˚C and 195V to 253V.
10. The outdoor unit of an air conditioner as claimed in claim 1, wherein the exhaust fan
starts functioning simultaneously with the compressor.
11. The outdoor unit of an air conditioner as claimed in claim 1, wherein the exhaust fan is
provided with a mesh in its front that is in contact with the ambient atmosphere.