Title of Invention

AN INLET APPARATUS FOR A COMPRESSOR

Abstract An inlet for a compressor having a housing defining a generally C-shaped inlet opening and a rotor cavity configured to contain first and second rotors is provided. The inlet includes an inlet duct defining an inlet opening and a generally C-shaped outlet opening. The inlet duct has an inner wall defining a cavity operable to communicate airflow between the inlet opening and the generally C-shaped outlet opening. The generally C-shaped outlet opening of the inlet duct is substantially similar to the shape of the generally C-shaped inlet opening of the housing. The inner wall includes a floor portion and a roof portion. At least a portion of the floor portion is contoured to impart a velocity component to the airflow complementary to the tangential velocity of each of the first and second rotors during rotation of the first and second rotors.
Full Text 1
COMPRESSOR INLET DUCT
TECHNICAL FIELD
[0001] The present invention relates to an inlet duct for a compressor or
supercharger.
BACKGROUND OF THE INVENTION
[0002] Compressors or superchargers may be mounted to an internal combustion
engine to increase the performance thereof. The compressor is operable to induct air
through an inlet duct to interleaved and counter-rotating first and second rotors. The first
and second rotors cooperate to increase the volume of air communicated to the internal
combustion engine, thereby increasing the volumetric efficiency of the internal
combustion engine.
SUMMARY OF THE INVENTION
[0003] An inlet apparatus for a compressor having a housing defining a
generally C-shaped inlet opening and a rotor cavity configured to contain interleaved,
counter-rotating first and second rotors is provided. The inlet apparatus includes an
inlet duct positioned upstream of the compressor and defining an inlet opening and a
generally C-shaped outlet opening. The inlet duct has an inner wall defining a cavity
operable to communicate airflow between the inlet opening and the generally C-shaped
outlet opening of the inlet duct. The generally C-shaped outlet opening of the inlet duct
is substantially similar to the shape of the generally C-shaped inlet opening of the
housing. The inner wall includes a floor portion and a roof portion each extending
from the inlet opening to the outlet opening. At least a portion of the floor is contoured
to impart a velocity component to the airflow complementary to the tangential velocity
of each of the first and second rotors during rotation of the first and second rotors.
[0004] The inlet duct may further include first and second ridges formed
centrally on the respective floor and roof portions each extending toward the outlet

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opening of the inlet duct. The first and second ridges preferably increase in at least one
of height and width moving toward the outlet opening of the inlet duct. The first and
second ridges are operable to impart a velocity component to the airflow
complementary to the tangential velocity of each of the first and second rotors during
rotation of the first and second rotors.
[0005] The above features and advantages and other features and advantages of
the present invention are readily apparent from the following detailed description of the
best modes for carrying out the invention when taken in connection with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Figure 1 is a bottom view of a portion of a supercharger or compressor
having an inlet duct mounted thereto;
[0007] Figure 2 is a perspective view of the compressor of Figure 1, with the inlet
duct removed, illustrating a first and second rotor;
[0008] Figure 3 is a perspective sectional view of the inlet duct of Figure 1; and
[0009] Figure 4 is a perspective view of an alternate embodiment of the inlet duct
of Figures 1 and 3, illustrating an alternate position for a bypass passage.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0010] Referring to the drawings wherein like reference numbers correspond to
like or similar components throughout the several figures, there is shown in Figure 1 a
supercharger or compressor assembly 10. The compressor assembly 10 is configured to
mount to an internal combustion engine, not shown. Those skilled in the art of engine
design will recognize that the compressor assembly 10 can be used to increase the
volumetric efficiency of an internal combustion engine, thereby increasing the
performance thereof. The compressor assembly 10 includes a compressor 12 and an inlet
duct 14. The compressor 12 includes a housing 16 configured to contain internal
components of the compressor 12. The housing 16 is preferably formed from cast metal,
such as aluminum or magnesium. The inlet duct 14 is mounted to the housing 16 via a

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plurality of fasteners 18. The inlet duct 14 may be formed integrally with the housing 16.
The inlet duct 14 is preferably formed from cast metal such as aluminum or magnesium;
however, the inlet duct 14 may be formed from a plastic or composite material while
remaining within the scope of that which is claimed.
[0011] A throttle body 20 is mounted with respect to the inlet duct 14 and is
operable to vary the amount of airflow, indicated as arrow 22, entering the inlet duct 14.
A bypass assembly 24 is mounted with respect to the inlet duct 14 and is operable to
selectively divert airflow 22 from the compressor 12 during certain modes of engine
operation, such as light load engine operation. The bypass assembly 24 includes an
actuator 26 operable to selectively and variably open a valve 28 disposed within a bypass
passage 30 defined by the inlet duct 14.
[0012] Referring to Figure 2, and with continued reference to Figure 1, there is
shown the compressor 12 with the inlet duct 14 removed. The housing 16 defines an
inlet opening 32. The inlet opening 32 is generally C-shaped in form and is operable to
communicate airflow 22 to a rotor cavity 34. The rotor cavity 34 is defined by the
housing 16 and is configured to contain a first and second rotor 36 and 38, respectively,
therein. The first and second rotors 36 and 38 are interleaved and are rotatably supported
within the rotor cavity 34 by a rotor bearing support 39. The rotor bearing support 39 is
formed integrally with the housing 16. The first and second rotors 36 and 38 counter-
rotate as indicated by arrows 40 and are operable to convey volumes of air from the inlet
opening 32 to an outlet opening, not shown, for subsequent introduction to the internal
combustion engine.
[0013] Referring to Figure 3, and with continued reference to Figures 1 and 2,
there is shown a sectional view of the inlet duct 14 of Figure 1. The inlet duct 14 has
an inner wall 42 that defines a cavity 44 operable to convey airflow 22 between an inlet
opening 46 and an outlet opening 48, each defined by the inlet duct 14. The inner wall
42 includes a floor portion 50 and a roof portion 52. Additionally, a sidewall portion
54 interconnects the floor portion 50 and the roof portion 52. A portion 56 of the floor
portion 50 is raised in the area of the rotor bearing support 39, shown in Figure 2, such
that the outlet opening 48 is generally C-shaped and substantially similar to the shape of

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the generally C-shaped inlet opening 32 of the housing 16. As shown in Figure 3, the
portion 56 of the floor portion 50 is raised immediately downstream from the throttle
body 20 and increases in height toward the outlet opening 48. Portions 58 of the floor
portion 50 are contoured to impart a velocity component to the airflow 22
complementary to the tangential velocity of each of the first and second rotors 36 and
38, shown in Figure 2, during rotation of the first and second rotors 36 and 38. For
instances where the inlet duct 14 is formed separately and mounted to the housing 16, the
perimeter of the outlet opening 48 of the inlet duct 14 should be at or within the contour
of the generally C-shaped inlet opening 32 to avoid the potential for turbulence caused
by mismatch between the two components.
[0014] A first ridge 60 is formed centrally on the floor portion 50 and extends
toward the outlet opening 48 of the inlet duct 14. The first ridge 60 is preferably
formed with a generally triangular cross-section with increasing height and width
moving toward the outlet opening 48 of the inlet duct 14. The first ridge 60 is operable
to impart a velocity component to said airflow 22 complementary to the tangential
velocity of each of the first and second rotors 36 and 38 during rotation of the first and
second rotors 36 and 38. The first ridge 60 is preferably positioned immediately
downstream of the bypass passage 30.
[0015] Similarly, a second ridge 62 is formed centrally on the roof portion 52
and extends toward the outlet opening 48 of the inlet duct 14. The second ridge 62 is
preferably formed with a generally triangular cross-section with increasing height and
width moving toward the outlet opening 48 of the inlet duct 14. The second ridge 62 is
operable to impart a velocity component to said airflow 22 complementary to the
tangential velocity of each of the first and second rotors 36 and 38 during rotation of
the first and second rotors 36 and 38. Preferably the first and second ridges 60 and 62
are separated, at least initially, to allow the airflow 22 on each side of the first and
second ridges 60 and 62 to equalize; however, the first and second ridges 60 and 62 can
be designed to converge to form a septum at the outlet opening 48 of the inlet duct 14.

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[0016] In instances where the throttle body 20 is tilted with respect to the inlet
duct 14, the airflow 22 may be biased to one side of the inlet duct 14 by the throttle
body 20. In this case, the inner wall 42 may be shaped to bias the airflow 22 to the
other side to balance the distribution of airflow 22 within the inlet duct prior to entering
the inlet opening 32 of the compressor 12, shown in Figure 2.
[0017] Referring to Figure 4, there is shown an alternate embodiment of the
inlet duct 14 of Figures 1 and 3, indicated at 14A. The inlet duct 14A has substantially
the same structure as the inlet duct 14, with the exception that a bypass passage 30A is
defined by the inlet duct 14A and extends through the side wall 54 of the inlet duct.
Since the bypass passage 30A does not intersect the floor portion 50, the first ridge 60
may extend from any point between the inlet opening 46, shown in Figure 3, and the
outlet opening 48 of the inlet duct.
[0018] While the best modes for carrying out the invention have been described
in detail, those familiar with the art to which this invention relates will recognize various
alternative designs and embodiments for practicing the invention within the scope of the
appended claims.

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CLAIMS
1. An inlet apparatus for a compressor having a housing defining a
generally C-shaped inlet opening and a rotor cavity configured to contain interleaved,
counter-rotating first and second rotors, the inlet apparatus comprising:
an inlet duct positioned upstream of the compressor defining an
inlet opening and a generally C-shaped outlet opening;
wherein said inlet duct has an inner wall defining a cavity operable
to communicate airflow between said inlet opening and said generally C-shaped outlet
opening of said inlet duct;
wherein said generally C-shaped outlet opening of said inlet duct is
substantially similar to the shape of the generally C-shaped inlet opening of the housing;
wherein said inner wall includes a floor portion and a roof portion,
said floor portion and said roof portion extending from said inlet opening to said outlet
opening; and
wherein at least a portion of said floor portion is contoured to
impart a velocity component to said airflow complementary to the tangential velocity of
each of the first and second rotors during rotation of the first and second rotors.
2. The inlet apparatus of claim 1, further comprising:
a first ridge formed centrally on said floor portion and extending
toward said outlet opening of said inlet duct;
wherein said first ridge increases in at least one of height and width
moving toward said outlet opening of said inlet duct; and
wherein said first ridge is operable to impart a velocity component
to said airflow complementary to the tangential velocity of each of the first and second
rotors during rotation of the first and second rotors.
3. The inlet apparatus of claim 1, further comprising:

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a second ridge formed centrally on said roof portion and extending
toward said outlet opening of said inlet duct;
wherein said second ridge increases in at least one of height and
width moving toward said outlet opening of said inlet duct; and
wherein said second ridge is operable to impart a velocity
component to said airflow complementary to the tangential velocity of each of the first
and second rotors during rotation of the first and second rotors.
4. The inlet apparatus of claim 2, wherein said first ridge is generally
triangular in cross section.
5. The inlet apparatus of claim 3, wherein said second ridge is
generally triangular in cross section.
6. The inlet apparatus of claim 1, wherein said portion of said floor
portion is raised immediately downstream from said inlet opening of said inlet duct and
increases in height toward said outlet opening of said inlet duct.
7. The inlet apparatus of claim 1, wherein said inlet duct is mounted
to the housing.
8. The inlet apparatus of claim 1, wherein said inlet duct defines a
bypass passage that extends through said floor portion.
9. The inlet apparatus of claim 1, wherein said inner wall includes a
sidewall portion interconnecting said floor portion and said roof portion and wherein said
inlet duct defines a bypass passage that extends through said sidewall portion.
10. A compressor assembly comprising:

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a housing defining a generally C-shaped inlet opening and a rotor
cavity;
wherein said generally C-shaped inlet opening is operable to
communicate airflow to said rotor cavity;
a first rotor interleaved with a second rotor, said first and second
rotors being rotatably contained within said rotor cavity;
wherein said first and second rotors are configured to counter-
rotate;
an inlet duct positioned upstream of said housing, said inlet duct
defining an inlet opening and a generally C-shaped outlet opening;
wherein said inlet duct has an inner wall defining a cavity operable
to communicate airflow between said inlet opening and said generally C-shaped outlet
opening of said inlet duct;
wherein said generally C-shaped outlet opening of said inlet duct is
substantially similar to the shape of said generally C-shaped inlet opening of said
housing;
wherein said inner wall includes a floor portion and a roof portion,
said floor portion and said roof portion extending from said inlet opening to said outlet
opening; and
wherein at least a portion of said floor portion is contoured to
impart a velocity component to said airflow complementary to the tangential velocity of
each of said first and second rotors during rotation of said first and second rotors.
11. The compressor assembly of claim 10, wherein said inlet duct
further includes:
a first ridge formed centrally on said floor portion and extending
toward said outlet opening of said inlet duct;
wherein said first ridge increases in at least one of height and width
moving toward said outlet opening of said inlet duct; and

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wherein said first ridge is operable to impart a velocity component
to said airflow complementary to the tangential velocity of each of said first and second
rotors during rotation of said first and second rotors.
12. The compressor assembly of claim 10, wherein said inlet duct
further includes:
a second ridge formed centrally on said roof portion and extending
toward said outlet opening of said inlet duct;
wherein said second ridge increases in at least one of height and
width moving toward said outlet opening of said inlet duct; and
wherein said second ridge is operable to impart a velocity
component to said airflow complementary to the tangential velocity of each of said first
and second rotors during rotation of said first and second rotors.
13. The inlet section of claim 11, wherein said first ridge is generally
triangular in cross section.
14. The inlet section of claim 12, wherein said second ridge is
generally triangular in cross section.
15. An inlet for a compressor having a housing defining an inlet
opening and a rotor cavity configured to contain interleaved, counter-rotating first and
second rotors, the inlet comprising:
an inlet duct positioned upstream of the compressor defining an
inlet opening and an outlet opening;
wherein said inlet duct has an inner wall defining a cavity operable
to communicate airflow between said inlet opening of said inlet duct and said generally
C-shaped outlet opening of said inlet duct;

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wherein said inner wall includes a floor portion and a roof portion,
said floor portion and said roof portion extending from said inlet opening to said outlet
opening;
a first ridge formed centrally on said floor portion and extending
toward said outlet opening of said inlet duct;
a second ridge formed centrally on said roof portion and extending
toward said outlet opening of said inlet duct;
wherein said first and second ridges increase in at least one of
height and width moving toward said outlet opening of said inlet duct; and
wherein said first and second ridges are operable to impart a
velocity component to said airflow complementary to the tangential velocity of each of
the first and second rotors during rotation of the first and second rotors.
16. The inlet of claim 15, wherein said outlet opening of said inlet duct
is generally C-shaped and wherein said outlet opening of said inlet duct is substantially
similar to the shape of the inlet opening of the housing.
17. The inlet of claim 16, wherein at least a portion of said floor
portion is contoured to impart a velocity component to said airflow complementary to the
tangential velocity of each of the first and second rotors during rotation of the first and
second rotors.
18. The inlet of claim 15, wherein said inlet opening of said inlet duct
is configured to mount a throttle body.

An inlet for a compressor having a housing defining a generally C-shaped
inlet opening and a rotor cavity configured to contain first and second rotors is provided.
The inlet includes an inlet duct defining an inlet opening and a generally C-shaped outlet
opening. The inlet duct has an inner wall defining a cavity operable to communicate
airflow between the inlet opening and the generally C-shaped outlet opening. The
generally C-shaped outlet opening of the inlet duct is substantially similar to the shape of
the generally C-shaped inlet opening of the housing. The inner wall includes a floor
portion and a roof portion. At least a portion of the floor portion is contoured to impart a
velocity component to the airflow complementary to the tangential velocity of each of the
first and second rotors during rotation of the first and second rotors.

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=HjDYRfYPJgjUEhzrG/wuyg==&loc=wDBSZCsAt7zoiVrqcFJsRw==


Patent Number 270309
Indian Patent Application Number 466/KOL/2008
PG Journal Number 50/2015
Publication Date 11-Dec-2015
Grant Date 09-Dec-2015
Date of Filing 06-Mar-2008
Name of Patentee GM GLOBAL TECHNOLOGY OPERATIONS, INC.
Applicant Address 300 GM RENAISSANCE CENTER DETROIT, MICHIGAN
Inventors:
# Inventor's Name Inventor's Address
1 KO-JEN WU 1940 SPICEWAY DRIVE TROY, MICHIGAN 48098
2 WILLIAM F. SPRUIT 6327 STONEHEARTH PASS GRAND BLANC, MICHIGAN 48493
3 JIAN JUN ZHANG 4640 DUNBAR COURT ROCHESTER, MICHIGAN 48306
PCT International Classification Number F04C29/12; F04C18/08; F04C29/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 11/696,963 2007-04-05 U.S.A.