FORM 2
The Patents Act 1970
(39
1970)
&
The Patent Rules 2003
COMPLETE SPECIFICATION
(See Section 10 and rule 13)
TITLE OF THE INVENTION:
ENCLOSURE FOR SCREW COMPRESSOR WITH EFFICIENT
COOLING MECHANISM
APPLICANT:
APPLICANT NAME APPLICANT ADDRESS
KIRLOSKAR PNEUMATIC
COMPANY LIMITED.
PLOT NO.1, HADAPSAR
INDUSTRIAL ESTATE, HADAPSAR,
PUNE, MAHARASHTRA 411013
INVENTORS:
INVENTORS NAME INVENTORS ADDRESS
SETHURAMAN KUMARAPPAN PLOT NO.1, HADAPSAR
INDUSTRIAL ESTATE, HADAPSAR,
PUNE, MAHARASHTRA 411013
PREAMBLE OF THE DESCRIPTION:
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE
INVENTION AND THE MANNER IN WHICH IT IS PERFORMED
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A) TECHNICAL FIELD
[001] The present invention generally relates to a mechanical enclosure and
particularly relates to an enclosure for a screw compressor with an efficient cooling
mechanism to lower an operating temperature of the screw compressor.
B) BACKGROUND OF INVENTION
[002] The compressor assemblies mostly needs enclosure for various purposes
such providing stability and even for transportation without damaging internal
assembly. Current enclosure or canopies for compressors usually comprise a
number of corner stays, at least one for each corner of a mounting surface of the
base plate of the chassis, and a number of intermediate stays at the edge of the
mounting surface and in between the corners of the mounting surface. Both the
corner stays and the intermediate stays extend in the same direction from the
chassis, perpendicularly on the mounting surface.
[003] However, the conventional enclosures have limited application in heat
dissipation and generally, they serve as outer shell. Due to availability of the space
in the enclosures and their interaction with ambient conditions makes it a perfect
candidate for a heat dissipation entity.
[004] In the view of foregoing, there is a need for an enclosure for screw
compressor with an efficient cooling mechanism to lower an operating temperature
of the screw compressor.
[005] The above-mentioned shortcomings, disadvantages and problems are
addressed herein, as detailed below.
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C) OBJECT OF INVENTION
[006] The primary objective of the present invention is to provide an enclosure for
but not limited to a screw compressor with a heat dissipation assembly to improve a
cooling effect in the screw compressor during operation.
[007] Another objective of the present invention is to provide an enclosure for a
compressor assembly to lower a running temperature of the compressor.
[008] Yet another objective of the present invention is to provide an enclosure for
increase a heat transfer efficiency in the compressor assembly.
[009] These and other objects and advantages of the embodiments herein will
become readily apparent from the following detailed description taken in
conjunction with the accompanying drawings.
D) SUMMARY OF INVENTION
[0010] The various embodiments of the present invention provide an enclosure for
a screw compressor comprising an air inlet unit, a cooling unit and a baffle unit.
The air inlet unit comprises a suction box and is fitted to an enclosure body at a
preferred position. The cooling unit is connected to the enclosure body at a position
having angular as well as linear displacement with respect to air inlet unit. The
baffle unit comprises a vertical baffle connected inside the enclosure body in a
vertical position and a horizontal baffle connected inside the enclosure body in a
horizontal position. The vertical baffle and the horizontal baffle surround a hot air
exhaust assembly and provide a heat shield to a heat exchanger.
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[0011] According to one embodiment of the present invention, the cooling unit
comprises a cooling fan unit for heat exchanger, and a cooling fan unit for a motor
provide in the compressor.
[0012] According to one embodiment of the present invention, each cooling fan
unit comprises an inlet port and a fan behind inlet port to draw in a fresh ambient
air.
[0013] According to one embodiment of the present invention, the preferred
position of the air inlet unit is at aside wall of the enclosure body and arranging an
exhaust air outlet port in the hot air exhaust assembly on a top wall of the enclosure
body creating an angular displacement with respect to the air inlet unit. The
displacement between the air inlet unit and the cooling unit leads to a separation of
the cold ambient inlet air with the hot exhaust air.
[0014] According to one embodiment of the present invention, the air inlet unit
comprises a suction box holding a dry type filter arranged behind the suction box to
allow a filtered and fresh air flow into an airend of the compressor through an inlet
channel.
[0015] According to one embodiment of the present invention, the suction box
creates a cooling air flow region from the air inlet unit to the compressor resulting
in lowering of operational temperature of the compressor and the motor.
[0016] According to one embodiment of the present invention, the operation
temperature is reduced by 2℃-5℃.
[0017] These and other aspects of the embodiments herein will be better
appreciated and understood when considered in conjunction with the following
description and the accompanying drawings. It should be understood, however, that
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the following descriptions, while indicating preferred embodiments and numerous
specific details thereof, are given by way of illustration and not of limitation. Many
changes and modifications may be made within the scope of the embodiments
herein without departing from the spirit thereof, and the embodiments herein
include all such modifications.
E) BRIEF DESCRIPTION OF DRAWINGS
[0018] The other objects, features and advantages will occur to those skilled in the
art from the following description of the preferred embodiment and the
accompanying drawings in which:
[0019] FIG. 1a and 1b illustrates a front perspective of an enclosure for a screw
compressor, according to one embodiment of the present invention.
[0020] FIG. 2 illustrates a sectional view of the enclosure with a cooling
mechanism, according to one embodiment of the present invention.
[0021] FIG. 3 illustrates an exploded view of the air inlet unit in the enclosure,
according to one embodiment of the present invention.
[0022] FIG. 4a-4e illustrates a front view, a right side view, a rear view, a left side
view and a top view of the enclosure, according to one embodiment of the present
invention.
[0023] FIG. 5 illustrates a graphical representation of an element temperature or
operating temperature of the compressor after implementation of the present
invention.
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F) DETAILED DESCRIPTION OF THE EMBODIMENTS
[0024] In oil injected screw air compressor, the cooling air (fresh atmospheric air)
is needed for many components for its proper functioning. For main compression
element, the air is needed for generating pressurized air delivery, while
compression the air is getting heated and again cooled in a heat exchanger to
normal temperature, so that it is ready for application. If the air is preheated due to
other hot surfaces, than more energy is spent for cooling.
[0025] Similarly for the heat exchanger to cool the hot compressed air, fresh
atmospheric air is needed, the efficiency of the heat exchanger highly dependent on
the temperature of the atmospheric air. So, in order to maintain the efficiency of the
heat exchanger cooling air is not to be preheated.
[0026] For motor, the fresh atmospheric air is needed in order to have better
cooling, so that temperature rise on the bearings, windings and shaft seals are under
control. Thus, a preheating of cooling air to motor will increase the abovementioned
temperatures which will reduce the life of the motor, bearings, seal and
grease on the bearings.
[0027] Thus, in order to avoid a contact between a heated air flow and a cold air
inlet, a partition or seclusion mechanism is to be employed in the compressor
assembly. Since, the enclosure of the compressor has a lot of free space for
movement of the air, hence the same is utilized for creating an efficient barrier
between various air flow zones and also between the cold ambient air and a
preheated air flow.
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[0028] The enclosure 100 comprises an air inlet unit 101, a cooling unit 102 and a
baffle unit. The air inlet unit 101 comprises an suction box 106 and is fitted to an
enclosure body 105 at a preferred position as shown in FIG. 2. The air inlet unit
101 comprises a dry type filter 107 arranged behind the suction box 106 to allow a
filtered and fresh air flow into an airend 108 of the compressor through an inlet
channel 109. The inlet channel is arranged at a preferrable 90° angle with respect to
the suction box thus allowing a filtered air to pass through as shown in FIG. 3.
Furthermore, the air inlet unit is designed in a L-shaped bracket providing an air
flow access to the inlet channel as well as a zone surrounding the inlet channel, the
compressor, and the motor allowing operation of the inlet channel, the compressor,
and the motor at a lower (element) temperature as shown in FIG. 5. The fresh air is
isolated from a preheated air and the hot exhaust air through the baffle unit (103 &
104). The hot exhaust air from the motor and the heat exchanger is exited from the
top wall of the enclosure body through an exhaust port 110.
[0029] As shown in FIG. 1a and FIG. 1b, the cooling unit 102 is connected to the
enclosure body at a position having angular as well as linear displacement with
respect to air inlet unit 101. The cooling unit 102 comprises a cooling fan unit for
heat exchanger, a cooling fan unit for a motor provided in the compressor. Each
cooling fan unit comprises an inlet port and a fan behind inlet port to draw in a
fresh ambient air. The cooling unit draws a fresh air from ambience towards the
heat exchanger, the compressor and the motor to reduce their surface temperature
which in turn reduces their operating temperature. The reduction in the operating
temperature increases a working efficiency of the compressor and also, reduce a
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wear and tear of bearings as well as airend components which generally happens
due to interaction with heat for a prolonged period.
[0030] The baffle unit comprises a vertical baffle 103 connected inside the
enclosure body 105 in a vertical position and a horizontal baffle 104 connected
inside the enclosure body 105 in a horizontal position. The vertical baffle and the
horizontal baffle create a shielding between the heat exchanger and the compressor,
the motor and the inlet channel. The heat released from the heat exchanger during
the exchanging process increase the temperature of air flowing near the surface of
the motor and the compressor which increases the surface temperature and increase
the susceptibility of the motor and the compressor to failure after a prolonged
operation. The barrier created by the baffle unit keeps the temperature of the cold
air much lower than the conventional arrangement, thus increases an operational
period of the compressor and the motor further leading to increase in a working
efficiency of the compressor.
[0031] Ambient conditions for compressors:
[0032] An ambient condition for a compressor is the temperature/room temperature
of the surrounding air around the compressor. These temperatures are in the range
of 0°C to max 55°C.
[0033] Also, another parameter is the relative humidity. The compressor smooth
operation is mainly dependant on the ambient temperature. The ambient air is used
for the following purposes in the compressor,
a) A medium of compression being compressed and delivered as
pressurized air for application.
b) A cooling medium for the oil heat exchanger and air heat exchanger.
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c) A cooling medium for the main electric motor and fan motor.
[0034] Evidently, when the ambient air is being compressed, the temperature rises
and to cool the compressed air, an oil is injected into the compression chamber to
cool the air and remove the heat from air. The compressed air and the oil are then
further cooled in an air heat exchanger and an oil heat exchanger. The cooled
compressed air is further delivered to the application. The cooled oil is again used
in the circuit for cooling.
[0035] In traditional compressors, there is no separation of air passages, due to this
the air being compressed is preheated by the hot air coming from the motor, due to
this the temperature rise is further increased in the compression process. And more
cooling air is needed for the air and oil heat exchanger.
[0036] In traditional compressor, the cooling air is also taken from inside the
canopy, due to the preheating of the cooling air inside the canopy, there is always a
temperature difference of 2°C to 5°C. The cooling system performance is also
reduced due to preheated air approaching the heat exchangers than normal ambient
air which is at a lesser temperature.
[0037] In the present, the baffle unit creates a cooling air flow region from the air
inlet unit to the compressor resulting in lowering of operational temperature of the
compressor and the motor and the operating temperature is reduced by 2℃-5℃.
[0038] In the following detailed description, a reference is made to the
accompanying drawings that form a part hereof, and in which the specific
embodiments that may be practiced is shown by way of illustration. The
embodiments are described in sufficient detail to enable those skilled in the art to
practice the embodiments and it is to be understood that the logical, mechanical and
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other changes may be made without departing from the scope of the embodiments.
The following detailed description is therefore not to be taken in a limiting sense.
G) ADVANTAGES OF THE INVENTION
[0039] The present invention allows a main compression element to operate in a
lower temperature which increases a life of the seal/bearings and also less amount
of cooling air required compared to a traditional compressor. Further, through the
implementation of the present invention, lesser powered fans can be used as air
flow required is less which further reduces the fan noise. Also, the baffle unit has a
noise insulation, thus as noise emitted is absorbed by the insulation.
[0040] It is to be understood that the phraseology or terminology employed herein
is for the purpose of description and not of limitation. Therefore, while the
embodiments herein have been described in terms of preferred embodiments, those
skilled in the art will recognize that the embodiments herein can be practiced with
modification within the spirit and scope of the claims.
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We Claim:
1. An enclosure for a screw compressor comprising:
an air inlet unit, wherein the air inlet unit comprises an inlet filter and a suction
box, wherein the suction box and is fitted to an enclosure body at a preferred
position;
a cooling unit, wherein the cooling unit is connected to the enclosure body at a
position having angular as well as linear displacement with respect to air inlet
unit;
a baffle unit, wherein the baffle unit comprises a vertical baffle connected inside
the enclosure body in a vertical position and a horizontal baffle connected inside
the enclosure body in a horizontal position;
wherein the vertical baffle and the horizontal baffle surround a hot air exhaust
assembly and provide a heat shield to a heat exchanger.
2. The enclosure as claimed in claim 1, wherein the cooling unit comprises a
cooling fan unit for heat exchanger, a cooling fan unit for a motor and a cooling
fan unit for a compression element provide in the compressor.
3. The enclosure as claimed in claim 2, wherein each cooling fan unit comprises an
inlet port and a fan behind inlet port to draw in a fresh ambient air.
4. The enclosure as claimed in claim 1, wherein the preferred position of the
suction box is a side wall of the enclosure body and arranging an exhaust air
outlet port in the hot air exhaust assembly on a top wall of the enclosure body
creating an angular displacement with respect to the suction box, wherein the
displacement between the air inlet unit and the cooling unit leads to a separation
of the cold ambient inlet air with the hot exhaust air.
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5. The enclosure as claimed in claim 1, wherein the air inlet unit comprises a dry
type filter arranged behind the suction box to allow a filtered and fresh air flow
into an airend of the compressor through an inlet channel.
6. The enclosure as claimed in claim 1, wherein the baffle unit creates a cooling air
flow region from the air inlet unit to the compressor resulting in lowering of
operational temperature of the compressor and the motor.
7. The enclosure as claimed in claim 6, wherein the operation temperature is
reduced by 2℃-5℃.