FORM 2
The Patents Act 1970
(39 of 1970)
&
The Patent Rules 2003
COMPLETE SPECIFICATION
(See Section 10 and rule 13)
TITLE OF THE INVENTION:
SCREW AIR COMPRESSOR WITH MULTI-AXIAL SUCTION PORT
APPLICANT:
APPLICANT NAME APPLICANT ADDRESS
KIRLOSKAR PNEUMATIC
COMPANY LIMITED.
PLOT NO.1, HADAPSAR
INDUSTRIAL ESTATE, HADAPSAR,
PUNE, MAHARASHTRA 411013
INVENTORS:
INVENTORS NAME INVENTORS ADDRESS
SHUBHANKAR TANKHIWALE PLOT NO.1, HADAPSAR
INDUSTRIAL ESTATE, HADAPSAR,
PUNE, MAHARASHTRA 411013
AKASH DAGWAR 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 an mechanical apparatus and
particularly relates to a screw air compressor with multi-axial suction.
B) BACKGROUND OF INVENTION
[002] A rotary-screw compressor is a type of compressor that works on a principle
of a rotary-type positive-displacement mechanism. These compressors are common
in industrial applications and replace more traditional piston compressors where
larger volumes of compressed gas are needed, e.g. for large refrigeration cycles
such as chillers, or for compressed air systems to operate air-driven tools such as
jackhammers and impact wrenches. For smaller rotor sizes the inherent leakage in
the rotors becomes much more significant, leading to this type of mechanism being
less suitable for smaller compressors than piston compressors.
[003] The conventional rotary screw compressors are improved in terms of
efficiency and function. One of such prior arts discloses a rotary-screw air
compressor having a separator, a cooler fan assembly, and a mounting apparatus.
The separator has a first chamber and a second chamber. The first chamber
separates compressed air and coolant. The second chamber separates compressed
air and suspended oil particles. The separator is disposed in a chasm formed by a
first platform. The mounting apparatus elevates a motor and air end vertically
above and spatially apart from the separator. A cooler fan assembly is vertically
above the motor and air end. The cooler fan assembly has a first heat exchanger
vertically above a second heat exchanger.
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[004] The said prior art and similar conventional rotary screw compressors have
either an entirely radial or axial type suction port design thus leading to an issue of
sudden pressure drop which reduces the compression efficiency.
[005] In the view of foregoing, there is a need for a rotary screw air compressor
which has a unique mechanism to counter a sudden pressure drop.
[006] The above-mentioned shortcomings, disadvantages and problems are
addressed herein, as detailed below.
C) OBJECT OF INVENTION
[007] The primary objective of the present invention is to provide a rotary screw
air compressor which has a unique mechanism to counter a sudden pressure drop.
[008] Another objective of the present invention is to provide a rotary screw air
compressor with lowest entry pressure drop and easy assembly integration.
[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 a rotary screw air
compressor comprising a suction unit, a compressor with a discharge unit. The
suction unit comprises a multi-axial suction port. The compressor is flanged to the
suction unit and comprises a pair of rotors covered in a rotor housing. The
discharge unit is connected to a distal end of the compressor. The suction unit
provides air inlet into the compressor in an axial direction sucked through a radial
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suction port. The radial suction port and a set of axial suction ports form the multiaxial
suction port.
[0011] According to one embodiment of the present invention, the suction unit
comprises a suction flange, a radial suction port housing, an end cover for the radial
suction port housing and an oil injection to a suction bearing. The suction flange is
provided around the radial suction port.
[0012] According to one embodiment of the present invention, the radial suction
port is connected to the pair of axial suction ports through a channel with gradually
chipped inner walls for altering an inlet air pressure in a gradual manner to counter
an air pressure dropping.
[0013] According to one embodiment of the present invention, the discharge unit
comprises an oil injection to a discharge bearing connected to a discharge port, a
discharge flange connected to the discharge port, a seal cover and a driving shaft.
[0014] According to one embodiment of the present invention, each axial suction
port is aligned with a rotor to create an air flow with a directed and controlled
pressure.
[0015] 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
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.
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E) BRIEF DESCRIPTION OF DRAWINGS
[0016] 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:
[0017] FIG. 1a illustrates a perspective view of a rotary screw air compressor,
according to one embodiment of the present invention.
[0018] FIG. 1b illustrates an isometric view of a suction unit in the rotary screw
compressor, according to one embodiment of the present invention.
[0019] FIG. 1c and 1d illustrates a left side and a right side perspective view of the
compressor with a discharge unit respectively, according to one embodiment of the
present invention.
[0020] FIG. 2a-2c illustrates a side view of a cut section, an isometric view of the
cut section and a front view of the suction unit, according to one embodiment of the
present invention.
F) DETAILED DESCRIPTION OF THE EMBODIMENTS
[0021] 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
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.
[0022] Conventionally the rotary screw compressors have either a radial suction or
an axial suction of air and after the suction, the air is transferred to the counter
rotating rotors for compression. Sometimes, the transfer from the suction port to a
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pressure chamber created by the rotor leading to drop in pressure thus leading to
irregular compression and thus reduces the overall compression efficiency.
[0023] The present rotary screw air compressor uses both radial and axial suction to
create a gradual pressure building before the air is transferred in the compressor
unit. As shown in FIG. 1a-1d, the rotary screw air compressor 100 comprising a
suction unit 101 and a compressor with discharge unit 102. The suction unit 101
comprises a multi-axial suction port. The compressor with discharge unit 102 is
flanged to the suction unit 101 and comprises a pair of rotors 103 covered in a rotor
housing 104. The compressor with discharge unit 102 is connected to a seal cover
113 and driving shaft 114. The suction unit 101 provides air inlet into the
compressor unit in an axial direction sucked through a radial suction port. The
radial suction port 105 and a set of axial suction ports 108 form the multi-axial
suction port as shown in FIG. 2a-2c. The suction unit 101 further comprises a
suction flange 107, a radial suction housing 106, an end cover 109 for the radial
suction port housing and an oil injection port 110 to a suction bearing. The suction
flange is provided around the radial suction port. The compressor with discharge
unit 102 comprises an oil injection port 111 to a discharge bearing connected to a
discharge port, a discharge flange 112 connected to the discharge port also the
driving parts like a seal cover 113 and a driving shaft 114.
[0024] According to one embodiment of the present invention, an air or air mixture
is sucked into the said rotary screw compressor through the radial suction port. The
radial suction port is connected to the pair of axial suction ports through a channel
with gradually chipped inner walls for altering an inlet air pressure in a gradual
manner to counter an air pressure dropping. The channel forms an L-bend from the
radial suction port to the axial suction port leading to increase in an air pressure.
The ladder like chipping on inner walls of the channel work as rivets to further
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modulate or decrease the air pressure. The gradual decrease in the air pressure in
the channel leads to countering of any sudden drop in the pressure while
transferring to the rotor assembly, hence improving the overall compression
efficiency. An improvement of twin-screw compressors is based on specific power
consumption which is defined as the power consumption per unit volume flow rate.
Without affecting the specific power consumption, the invention ensures an added
advantage of package compatibility. Power required for multi-axial suction port is
58.21 kW for the free air delivery of 16.8 m3/min. Therefore, the specific power
comes out to be 3.46 kW/m3/min.
G) ADVANTAGES OF THE INVENTION
[0025] The present rotary screw compressor provides a controlled and manipulated
air flow from a suction port to the rotor assembly, thus improving a reliability of
compression functioning and lowering wearing of the compressor assembly due to
pressure differential.
[0026] 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.

Claims:
I/We Claim:
1. A rotary screw air compressor comprising:
a suction unit, wherein the suction unit comprises a multi-axial suction port;
a compressor with a discharge unit, wherein the compressor unit is flanged to
the suction unit and comprises a pair of rotors covered in a rotor housing,
wherein the discharge unit is connected to a distal end of the compressor unit;
wherein, the suction unit provides air inlet into the compressor unit in an axial
direction sucked through a radial suction port, wherein the radial suction port
and a set of axial suction ports form the multi-axial suction port.
2. The air compressor as claimed in claim 1, wherein the suction unit comprises a
suction flange, a radial suction port housing, an end cover for the radial suction
port housing and an oil injection to a suction bearing, wherein the suction
flange is provided around the radial suction port.
3. The air compressor as claimed in claim 1, wherein the radial suction port is
connected to the pair of axial suction ports through a channel with a gradually
chipped inner walls for altering an inlet air pressure in a gradual manner to
counter an air pressure dropping.
4. The air compressor as claimed in claim 1, wherein the discharge unit comprises
an oil injection to a discharge bearing connected to a discharge port, a discharge
flange connected to the discharge port, a seal cover and a driving shaft.

5. The air compressor as claimed in claim 1, wherein each axial suction port is
aligned with a rotor to create an air flow with a directed and controlled pressure.