U.S. patent number RE40,344 [Application Number 10/681,353] was granted by the patent office on 2008-05-27 for scroll machine with ported orbiting scroll member.
This patent grant is currently assigned to Emerson Climate Technologies, Inc.. Invention is credited to Roy J. Doepker, Michael M. Perevozchikov.
United States Patent |
RE40,344 |
Perevozchikov , et
al. |
May 27, 2008 |
Scroll machine with ported orbiting scroll member
Abstract
A scroll compressor includes a fluid injection system. The fluid
injection system includes a fluid passage which extends from a
position outside of the shell of the compressor to the fluid
pockets created by the wraps of the scroll members. The fluid
passage extends through the orbiting scroll member. The fluid
injection system can be used to inject gaseous or liquid
refrigerant, lubricant or the fluid injection system can be used to
vent the moving pocket to the suction area of the compressor for
capacity modulation.
Inventors: |
Perevozchikov; Michael M. (Tipp
City, OH), Doepker; Roy J. (Lima, OH) |
Assignee: |
Emerson Climate Technologies,
Inc. (Sidney, OH)
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Family
ID: |
24562341 |
Appl.
No.: |
10/681,353 |
Filed: |
October 8, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
09639004 |
Aug 15, 2000 |
06350111 |
Feb 26, 2002 |
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Current U.S.
Class: |
417/440;
418/55.6; 418/87; 418/99 |
Current CPC
Class: |
F04C
18/0261 (20130101); F04C 23/008 (20130101); F04C
29/042 (20130101); F04C 2240/603 (20130101) |
Current International
Class: |
F04B
23/00 (20060101); F04B 41/00 (20060101) |
Field of
Search: |
;418/55.1-55.6,84,87,99
;417/310,440 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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6-26472 |
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Feb 1994 |
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JP |
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06026472 |
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Feb 1994 |
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JP |
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Other References
European Search Report for Application No. EP 01 30 6855; Nov. 13,
2001; 1 Page. cited by other .
English language Abstract for JP 6-26472, 01.02.94, 1 Page. cited
by other .
English language Abstract for JP 10037879, 13.02.98, 1 Page. cited
by other.
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Primary Examiner: Trieu; Theresa
Attorney, Agent or Firm: Harness, Dicckey & Pierce,
P.L.C.
Claims
What is claimed is:
1. A scroll-type compressor for handling a working fluid, said
compressor comprising: a shell having a suction zone and a
discharge zone; a first scroll member disposed in said shell and
having a first scroll wrap extending from a first end plate; a
second scroll member disposed in said shell and having a second
scroll wrap extending from a second end plate, said second scroll
wrap being intermeshed with said first scroll wrap to define a
plurality of closed pockets; a drive mechanism for causing said
second scroll member to orbit with respect to said first scroll
member, said plurality of pockets moving from a radial outer
position in said suction zone to a central position in said
discharge zone; .Iadd.a vapor injection system including .Iaddend.a
fluid circuit in communication with at least one of said plurality
of pockets, said fluid circuit including a fluid passage extending
from said one pocket to a position outside said shell .Iadd.for
injecting vapor into said one pocket and increasing a capacity of
the compressor.Iaddend., said fluid passage extending through said
second scroll member; and a valve for controlling fluid flow
through said fluid passage.
2. The scroll-type compressor according to claim 1, wherein said
valve is disposed within said shell.
3. The scroll-type compressor according to claim 2, wherein said
valve is controlled by a pressurized fluid from outside said
shell.
4. A scroll-type compressor for handling a working fluid.[.;.].
.Iadd., .Iaddend.said compressor comprising: a shell; a
non-orbiting scroll member disposed within said shell and having a
nonorbiting scroll wrap extending from a non-orbiting end plate; an
orbiting scroll member disposed within said shell and having an
orbiting scroll wrap extending from an orbiting end plate, said
orbiting scroll wrap being intermeshed with said non-orbiting
scroll member to define a plurality of closed pockets; a drive
mechanism for causing said orbiting scroll member to orbit with
respect to said non-orbiting scroll member, said plurality of
closed pockets moving from a radial outer position where said
working fluid is at a suction pressure to a radially inner central
position where said working fluid is at a higher discharge pressure
during said orbital movement; .Iadd.a vapor injection system
including .Iaddend.a fluid circuit in communication with at least
one of said plurality of moving pockets, said fluid circuit
including a fluid passage extending from said one pocket to a
position outside of said shell .Iadd.for injecting vapor into said
one pocket and increasing a capacity of the compressor.Iaddend.,
said fluid pocket extending through said orbiting scroll member;
and a valve for controlling fluid flow through said fluid
passage.
5. The scroll-type compressor according to claim 4, wherein said
valve is disposed within said shell.
6. The scroll-type compressor according to claim 5, wherein said
valve is controlled by a pressurized fluid from outside said
shell.
7. A scroll-type compressor for handling a working fluid, said
compressor comprising: a shell having a suction zone and a
discharge zone; a first scroll member disposed in said shell and
having a first scroll wrap extending from a first end plate; a
second scroll member disposed in said shell and having a second
scroll wrap extending from a second end plate, said second scroll
wrap being intermeshed with said first scroll wrap to define a
plurality of closed pockets; a drive mechanism for causing said
second scroll member to orbit with respect to said first scroll
member, said plurality of pockets moving from a radial outer
position in said suction zone to a central position in said
discharge zone; a fluid circuit in communication with at least one
of said plurality of pockets, said fluid circuit including a fluid
passage extending from said one pocket to a position outside said
shell, said fluid passage extending through said second scroll
member; a housing disposed within said shell, said housing
supporting said second scroll member, said fluid passage extending
through said housing; and a valve disposed within said housing,
said valve controlling fluid flow through said fluid passage.
8. The scroll-type compressor according to claim 1, wherein said
valve is controlled by a pressurized fluid from outside said
shell.
9. A scroll-type compressor for handling a working fluid; said
compressor comprising: a shell; a non-orbiting scroll member
disposed within said shell and having a nonorbiting scroll wrap
extending from a non-orbiting end plate; an orbiting scroll member
disposed within said shell and having an orbiting scroll wrap
extending from an orbiting end plate, said orbiting scroll wrap
being intermeshed with said non-orbiting scroll member to define a
plurality of closed pockets; a drive mechanism for causing said
orbiting scroll member to orbit with respect to said non-orbiting
scroll member, said plurality of closed pockets moving from a
radial outer position where said working fluid is at a suction
pressure to a radially inner central position where said working
fluid is at a higher discharge pressure during said orbital
movement; a fluid circuit in communication with at least one of
said plurality of moving pockets, said fluid circuit including a
fluid passage extending from said one pocket to a position outside
of said shell, said fluid pocket extending through said orbiting
scroll member; a housing disposed within said shell, said housing
supporting said orbiting scroll member, said fluid passage
extending through said housing; and a valve disposed within said
housing, said valve controlling fluid flow through said fluid
passage.
10. The scroll-type compressor according to claim 9, wherein said
valve is controlled by a pressurized fluid from outside said
shell.
11. A scroll-type compressor for handling a working fluid, said
compressor comprising: a shell having a suction zone and a
discharge zone; a first scroll member disposed in said shell and
having a first scroll wrap extending from a first end plate; a
second scroll member disposed in said shell and having a second
scroll wrap extending from a second end plate, said second scroll
wrap being intermeshed with said first scroll wrap to define a
plurality of closed pockets; a drive mechanism for causing said
second scroll member to orbit with respect to said first scroll
member, said plurality of pockets moving from a radial outer
position in said suction zone to a central position in said
discharge zone; a fluid circuit in communication with at least one
of said plurality of pockets, said fluid circuit including a fluid
passage extending from said one pocket to a position outside said
shell, said fluid passage extending through said second scroll
member; and a housing having a plurality of legs disposed within
said shell, said housing supporting said second scroll member, said
fluid passage extending through one of said legs of said
housing.
12. The scroll-type compressor according to claim 11, further
comprising a valve disposed within said housing, said valve
controlling fluid flow through said fluid passage.
13. The scroll-type compressor according to claim 12, wherein said
valve is controlled by a pressurized fluid from outside said
shell.
14. A scroll-type compressor for handling a working fluid; said
compressor comprising: a shell; a non-orbiting scroll member
disposed within said shell and having a nonorbiting scroll wrap
extending from a non-orbiting end plate; an orbiting scroll member
disposed within said shell and having an orbiting scroll wrap
extending from an orbiting end plate, said orbiting scroll wrap
being intermeshed with said non-orbiting scroll member to define a
plurality of closed pockets; a drive mechanism for causing said
orbiting scroll member to orbit with respect to said non-orbiting
scroll member, said plurality of closed pockets moving from a
radial outer position where said working fluid is at a suction
pressure to a radially inner central position where said working
fluid is at a higher discharge pressure during said orbital
movement; a fluid circuit in communication with at least one of
said plurality of moving pockets, said fluid circuit including a
fluid passage extending from said one pocket to a position outside
of said shell, said fluid pocket extending through said orbiting
scroll member; and a housing having a plurality of legs disposed
within said shell, said housing supporting said orbiting scroll
member, said fluid passage extending through one of said legs of
said housing.
15. The scroll-type compressor according to claim 14, further
comprising a valve disposed within said one leg of said housing,
said valve controlling fluid flow through said fluid passage.
16. The scroll-type compressor according to claim 15, wherein said
valve is controlled by a pressurized fluid from outside said
shell.
17. A scroll-type compressor for handling a working fluid, said
compressor comprising: a shell having a suction zone and a
discharge zone; a first scroll member disposed in said shell and
having a first scroll wrap extending from a first end plate; a
second scroll member disposed in said shell and having a second
scroll wrap extending from a second end plate, said second scroll
wrap being intermeshed with said first scroll wrap to defined a
plurality of closed pockets; a drive mechanism for causing said
second scroll member to orbit with respect to said first scroll
member, said plurality of pockets moving from a radial outer
position in said suction zone to a central position in said
discharge zone; a first circuit in communication with at least one
of said plurality of pockets, said fluid circuit including a fluid
passage extending from said one pocket to said suction zone of said
compressor, said fluid passage extending through said second scroll
member; .[.and.]. a housing disposed within said shell, said
housing supporting said second scroll member, said fluid passage
extending through said housing.Iadd.; and a valve disposed within
said housing, said valve controlling fluid flow through said fluid
passage.Iaddend..
.[.18. The scroll-type compressor according to claim 17, further
comprising a valve disposed within said housing, said valve
controlling fluid flow through said fluid passage..].
19. The scroll-type compressor according to claim .[.18.].
.Iadd.17.Iaddend., wherein said valve is controlled by a
pressurized fluid from outside said shell.
20. The scroll-type compressor according to claim .[.18.].
.Iadd.17.Iaddend., wherein said fluid passage is in communication
with an injection port extending through said shell and said valve
is movable between a first position where said one pocket
communicates with said suction zone of said compressor and a second
position where said one pocket communicates with said injection
port extending through said shell.
21. A scroll-type compressor for handling a working fluid, said
compressor comprising: a shell having a suction zone and a
discharge zone; a first scroll member disposed in said shell and
having a first scroll wrap extending from a first end plate; a
second scroll member disposed in said shell and having a second
scroll wrap extending from a second end plate, said second scroll
wrap being intermeshed with said first scroll wrap to define a
plurality of closed pockets; a drive mechanism for causing said
second scroll member to orbit with respect to said first scroll
member, said plurality of pockets moving from a radial outer
position in said suction zone to a central position in said
discharge zone; a fluid circuit in communication with at least one
of said plurality of pockets, said fluid circuit including a fluid
passage extending from said one pocket to said suction zone of said
compressor, said fluid passage extending through said second scroll
member; and a valve for controlling fluid flow through said fluid
passage; wherein; said valve is disposed within said shell; and
said valve is controlled by a pressurized fluid from outside said
shell.
22. The scroll-type compressor according to claim 21, wherein said
fluid passage is in communication with an injection port extending
through said shell and said valve is movable between a first
position where said one pocket communicates with said suction zone
of said compressor and a second position where said one pocket
communicates with said injection port extending through said
shell.
23. A scroll-type compressor for handling a working fluid, said
compressor comprising: a shell having a suction zone and a
discharge zone; a first scroll member disposed in said shell and
having a first scroll wrap extending from a first end plate; a
second scroll member disposed in said shell and having a second
scroll wrap extending from a second end plate, said second scroll
wrap being intermeshed with said first scroll wrap to define a
plurality of closed pockets; a drive mechanism for causing said
second scroll member to orbit with respect to said first scroll
member, said plurality of pockets moving from a radial outer
position in said suction zone to a central position in said
discharge zone; a fluid circuit in communication with at least one
of said plurality of pockets, said fluid circuit including a fluid
passage extending from said one pocket to said suction zone of said
compressor, said fluid passage extending through said second scroll
member; and a housing having a plurality of legs disposed within
said shell, said housing supporting said first scroll member, said
fluid passage extending through one of said legs of said
housing.
24. The scroll-type compressor according to claim 23, further
comprising a valve disposed within said housing, said valve
controlling fluid flow through said fluid passage.
25. The scroll-type compressor according to claim 24, wherein said
valve is controlled by a pressurized fluid from outside said shell.
Description
FIELD OF THE INVENTION
The present invention relates generally to scroll-type machines.
More particularly, the present invention relates to hermetic scroll
compressors incorporating a fluid injection system where the fluid
injection system utilizes a fluid passage extending through the end
plate of the orbiting scroll member.
BACKGROUND AND SUMMARY OF THE INVENTION
Refrigeration and air conditioning systems generally include a
compressor, a condenser, an expansion valve or an equivalent, and
an evaporator. These components are coupled in sequence in a
continuous flow path. A working fluid flows through the system and
alternates between a liquid phase and a vapor or gaseous phase.
A variety of compressor types have been used in refrigeration
systems, including but not limited to reciprocating compressors,
screw compressors and rotary compressors. Rotary type compressors
can include the various vane type compressors as scroll machines.
Scroll compressors are constructed using two scroll members with
each scroll member having an end plate and a spiral wrap. The
scroll members are mounted so that they may engage in relative
orbiting motion with respect to each other. During this orbiting
movement, the spiral wraps define a successive series of enclosed
spaces or pockets, each of which progressively decrease in size as
it moves inwardly from a radial outer position at a relatively low
suction pressure to a central position at a relatively high
pressure. The compressed gas exists from the enclosed space at the
central position through a discharge passage formed through the end
plate of one or the scroll members.
The designers for these scroll-type machines need to have access to
these enclosed spaces or pockets as they move between suction and
discharge for various reasons. One reason for accessing these
moving pockets is to inject oil into the pockets in order to
lubricate and cool the scroll members as they compress the fluid.
Another reason for accessing these moving pockets, for a
refrigerant compressor, is to inject liquid refrigerant to provide
cooling for the scroll members. Anther reason for accessing these
moving pockets is to connect these intermediate pockets to the
suction zone of the compressor in order to reduce the capacity of
the compressor in a capacity modulation system. Still another
reason for accessing these moving pockets is to inject an
additional quantity of the fluid being compressed in vapor form in
order to increase the compression ratio or capacity of the scroll
machine.
Various prior art methods have been utilized to gain access to
these moving pockets. When the access to these moving pockets does
not require access from outside the hermetic shell of the
compressor, such as oil injection and/or capacity modulation, the
access can be achieved through either the orbiting scroll or the
non-orbiting scroll, depending on the design intent for the
injection system. When the access to these moving pockets does
require access from outside the hermetic shell, such as liquid
injection and vapor injection systems, the access is provided
through the stationary or non-orbiting scroll due to the ease of
communicating with a stationary scroll member rather than the
moving orbiting scroll member.
The continued development for fluid injection systems include the
optimizing of the designs for gaining access to the moving pockets
of compressed fluid. The present invention provides the art with a
method of accessing the moving fluid pockets from outside the
hermetic shell of the compressor through a passage extending
through the end plate of the orbiting scroll member. Accessing the
moving pockets from outside the hermetic shell through the orbiting
scroll provides for less expensive and simpler assembly of the
scroll machine as well as less expensive machining requirements for
the scroll members.
Other advantages and objects of the present invention will become
apparent to those skilled in the art from the subsequent detailed
description, appended claims and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings which illustrate the best mode presently
contemplated for carrying out the present invention:
FIG. 1 is a vertical cross sectional view of a scroll compressor
incorporating a unique fluid injection system in accordance with
the present invention;
FIG. 2 is a plan view, partially in cross-section of the scroll
compressor shown in FIG. 1;
FIG. 3 is an enlarged cross-sectional view taken generally along
line 3-3 in FIG. 2 showing the injection system for the compressor
shown in FIG. 1;
FIG. 4 is a plan view, partially in cross-section, of a unique
fluid injection system in accordance with another embodiment of the
present invention;
FIG. 5 is an enlarged cross-sectional view taken generally alone
line 5-5 in FIG. 4 showing the injection system shown in FIG.
4;
FIG. 6 is a plan view, partially in cross-section, of a unique
fluid injection system in accordance with another embodiment of the
present invention; and
FIG. 7 is an enlarged cross-sectional view showing the injection
system shown in FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings in which like reference numerals
designate like or corresponding parts throughout the several views,
there is shown in FIG. 1 a hermetic shell compressor incorporating
the unique fluid injection system in accordance with the present
invention which is identified generally by the reference numeral
10. Scroll compressor 10 comprises a generally cylindrical hermetic
shell 12 having welded at the upper end thereof a cap 14 and at the
lower end thereof a base 16 having a plurality of mounting feet
(not shown) integrally formed therewith. Cap 14 is provided with a
refrigerant discharge fitting 18 which may have the usual discharge
valve therein (not shown). Other major elements affixed to shell 12
includes a transversely extending partition 20 which is welded
about its periphery at the same point cap 14 is welded to shell 12,
an inlet fitting 22, a main bearing housing 24 which is suitably
secured to shell 12 and a lower bearing housing 26 having a
plurality of radially outwardly extending legs each of which is
suitably secured to shell 12. A motor stator 28 which is generally
square in cross-section but with the corners rounded off is press
fit into shell 12. The flats between the rounded corners on stator
28 provide passageways between stator 28 and shell 12 which
facilitate the return flow of the lubricant from the top of shell
12 to its bottom.
A drive shaft or crankshaft 30 having an eccentric pin 32 at the
upper end thereof is rotatably journaled in a bearing 34 in main
bearing housing 24 and in a bearing 36 in lower bearing housing 26.
Crankshaft 30 has at the lower end thereof a relatively large
diameter concentric bore 38 which communicates with a radially
outwardly located smaller diameter bore 40 extending upwardly
therefrom to the top of crankshaft 30. Disposed within bore 38 is a
stirrer 42. The lower portion of the interior shell 12 is filled
with lubricating oil and bores 38 and 40 act as a pump to pump the
lubricating oil up crankshaft 30 and ultimately to all of the
various portions of compressor 10 which require lubrication.
Crankshaft 30 is relatively driven by an electric motor which
includes motor stator 28 having windings 44 passing therethrough
and a motor rotor 46 press fitted onto crankshaft 30 and having
upper and lower counterweights 48 and 50, respectively. A motor
protector 52, of the usual type, is provided in close proximity to
motor windings 44 so that if the motor exceeds its normal
temperature range, motor protector 52 will de-energize the
motor.
The upper surface of main bearing housing 24 is provided with an
annular flat thrust bearing surface 54 on which is disposed an
orbiting scroll member 56. Scroll member 56 comprises an end plate
58 having the usual spiral vane or wrap 60 on the upper surface
thereof and an annular flat thrust surface 62 on the lower surface
thereof. Projecting downwardly from the lower surface is a
cylindrical hub 64 having a journal bearing 66 therein and in which
is rotatively disposed a drive bushing 68 having an inner bore
within which crank pin 32 is drivingly disposed. Crank pin 32 has a
flat on one surface (not shown) which drivingly engages a flat
surface in a portion of the inner bore of drive bushing 68 to
provide a radially complaint drive arrangement such s shown in
assignee's U.S. Pat. No. 4,877,382, the disclosure of which is
incorporated herein by reference.
Wrap 60 meshes with a non-orbiting scroll wrap 72 forming part of a
non-orbiting scroll member 74. During orbital movement of orbiting
scroll member 56 with respect to non-orbiting scroll member 74
creates moving pockets of fluid which are compressed as the pocket
moves from a radially outer position to a central position of
scroll members 56 and 74. Non-orbiting scroll member 74 is mounted
to main bearing housing 24 in any desired manner which will provide
limited axial movement of non-orbiting scroll member 74. The
specific manner of such mounting is not critical to the present
invention. However, in the preferred embodiment, non-orbiting
scroll member 74 has a plurality of circumferentially spaced
mounting bosses 76 (see FIGS. 2 and 3), each having a flat upper
surface 78 and an axial bore 80. A sleeve 82 is slidably disposed
within bore 80 and sleeve 82 is bolted to main bearing housing 24
by a bolt 84. Bolt 84 has an enlarged head which engages upper
surface 78 to limit the axial upper or separating movement of
non-orbiting scroll member 74. Movement of non-orbiting scroll
member 74 is the opposite direction is limited by axial enlargement
of the lower tip surface of wrap 72 and the flat upper surface of
orbiting scroll member 56.
Non-orbiting scroll member 74 has a centrally disposed discharge
port 88 which is in fluid communication via an opening 90 in
partition 20 with a discharge muffler 92 defined by cap 14 and
partition 20. Fluid compressed by the moving pockets between scroll
wraps 60 and 72 discharges into discharge muffler 92 through port
88 and opening 90. Non-orbiting scroll member 74 has in the upper
surface thereof an annular recess 94 having parallel coaxial
sidewalls within which is sealingly disposed for relative axial
movement an annular seal assembly 96 which serves to isolate the
bottom of recess 94 so that it can be placed in fluid communication
with a source of intermediate fluid pressure by means of a
passageway 98. Non-orbiting scroll member 74 is thus axially biased
against orbiting scroll member 56 by the forces created by
discharge pressure acting on the central portion of non-orbiting
scroll member 74 and the forces created by intermediate fluid
pressure acting on the bottom of recess 94. This axial pressure
biasing, as well as the various techniques for supporting
non-orbiting scroll member 74 for limited axial movement, are
disclosed in much greater detail in assignee's aforementioned U.S.
Pat. No. 4,877,382.
Relative rotation of scroll members 56 and 74 is prevented by the
usual Oldham Coupling 100 having a pair of keys slidably disposed
in diametrically opposing slots in non-orbiting scroll member 74
and a second pair of keys slidably disposed in diametrically
opposed slots in orbiting scroll member 56.
Compressor 10 is preferably of the "low side" type in which suction
gas entering shell 12 is allowed, in part, to assist in cooling the
motor. So long as there is an adequate flow of returning suction
gas, the motor will remain within the desired temperature limits.
When this flow ceases, however, the loss of cooling will cause
motor protector 52 to trip and shut compressor 10 down.
The scroll compressor, as thus broadly described, is either known
in the art or it is the subject matter of other pending
applications for patent by Applicant's assignee. The details of
construction which incorporate the principles of the present
invention are those which deal with a unique fluid injection system
identified generally by reference numeral 110. Fluid injection
system 110 can be used to inject liquid refrigerant for cooling
purposes, vapor or gaseous refrigerant for capacity increase, oil
for lubrication and cooling or fluid injection system 110 can be
used for capacity modulation. The present invention, for exemplary
purposes, will be described using a vapor injection system as fluid
injection system 110 but it is to be understood that other fluids
could be injected or fluids can be vented using fluid injection
system 110.
Referring now to FIGS. 1-3, fluid injection system 110 comprises a
pair of fluid injection passages 112 extending through end plate 58
of orbiting scroll member 56, a pair of generally vertical fluid
passages 114 in main bearing housing 24, a generally circular
horizontal fluid passage 116 in main bearing housing 24, a
generally horizontal fluid passage 118 extending through one of the
legs of main bearing housing 24, a fluid injection port 120
extending through shell 12, and a fluid injection fitting 122
secured to the outside of shell 12.
Fluid injection passages 112 extend through end plate 58 of
orbiting scroll member 56. The positioning of the opening for
passages 112 on the wrap side of the end plate will be determined
by the positioning during the compression cycle that fluid is going
to be injected or released from a pair of the moving pockets
between wraps 60 and 72. The positioning of the opening for
passages 112 on thrust surface 62 of scroll member 56 will be such
that the opening of passages 112 will always be adjacent thrust
bearing surface 54 of main bearing housing 24 throughout the entire
orbital movement of orbiting scroll member 56. This feature is
described below as it relates to fluid passage 114.
Fluid passages 114 each extend vertically from thrust bearing
surface 54 to fluid passage 116. Each fluid passage 114 comprises a
counter bored portion 124 which opens up on thrust bearing surface
54. Counter bored portions 124 are sized such that fluid
communication is always maintaining with its respective fluid
injection hole 112 during all orbiting movement of orbiting scroll
member 56.
Generally circular horizontal passage 116 extends between the pair
of fluid passages 114 and horizontal fluid passage 118. Fluid
passage 118 extends generally horizontally through one of the legs
of main bearing housing 24. Fluid passage 118 opens to injection
port 120 which extends through shell 12. Fluid injection fitting
122 is secured to shell 12 by welding and it includes a central
bore 126 in fluid communication with port 120.
Thus, access from injection fitting 122 to the moving compression
pockets between scroll wraps 60 and 72 is provided through bore
126, through port 120, through passage 118, through passage 116,
through passage 114 and counter bore 124, and through passages 112.
Fluid can be injected into the moving pockets between scroll wraps
60 and 72 or fluid can be removed from the moving pockets between
scroll wraps 72 and 66 through fitting 122.
Referring now to FIGS. 4 and 5, a fluid injection system 210
according to another embodiment of the present invention is
illustrated. Fluid injection system 210 is similar to fluid
injection system 110 except that fluid injection system 210
incorporates an internal valve system 230 which can replace any
type of external valve system incorporated with fluid injection
system 110. Internal value system 230 is disposed inside shell 12
as opposed to an external system. Internal valve system 230
comprises a slider valve 232, a valve guide support 234, a valve
return spring 236 and an activating fitting 238.
Slider valve 232 is slidingly disposed within a bore 240 which
intersects with generally horizontal fluid passage 118. A pair of
seals 242 seal the fluid within fluid passage 118 from bore 240.
Slider valve 232 defines a vapor injection through hole 244 and a
modulation slot 246. Vapor injection through hole 244 is utilized
for providing vapor injection into the fluid pockets between scroll
wraps 60 and 72 to increase the capacity of the compressor.
Modulation slot 246 is utilized for providing delayed compression
by releasing the compressed fluid in the fluid pockets between
scroll wraps 60 and 72 to modulate or reduce the capacity of the
compressor. The combination of the vapor injection and the delayed
compression allows for an increase in the modulation of the
compressor when the full capacity of the compressor is with vapor
injection. Assuming a compressor without vapor injection operates
at 100% capacity and, with capacity modulation due to delayed
compression, the capacity is reduced to approximately 60%, the
incorporation of vapor injection will increase its capacity to
approximately 120%. When valve system 230 switches from vapor
injection to modulation, the capacity will reduce to the original
60%. Thus, a 60% capacity modulation (100% to 60%) becomes a 50%
capacity modulation (120% to 60%).
Valve guide support 234 is attached to an adjacent leg of main
bearing housing 24 and it defines bore 248 which slidingly receives
slider valve 232 and guides its movement. Valve return spring 236
is located between valve guide support 234 and slider valve 232 to
bias slider valve 232 into its vapor injection position as shown in
FIG. 4. Activating fitting 238 is in communication with one end of
bore 240 through a bore 250 in fitting 238, a port 252 in shell 12
and a passage 254 in the leg of main bearing housing 24. Bore 250
is connected to a source of pressurized fluid, such as the
discharge pressure of the compressor, through a valve such as a
solenoid valve. When this pressurized fluid is provided to the end
of bore 240, slider valve 232 moves from its position shown in FIG.
4 to a position where modulation slot 246 aligns with fluid passage
118 to permit modulation of the capacity of the compressor through
a port 260 extending through main bearing housing 24. A seal 256
isolates the pressurized fluid provided through activating fitting
238. When the vapor injection feature is again desired, the
pressurized fluid can be released from fitting 238 allowing valve
return spring 236 to again align vapor injection through hole with
passage 118 as shown in FIG. 4.
Referring now to FIGS. 6 and 7, a fluid injection system 310
according to another recombinant of the present invention is
illustrated. Fluid injection system 310 provides an alternative
method for accessing the moving pockets defined by wraps 60 and 72.
Fluid injection system 310 comprises the pair of fluid injection
passages 112, a pair of generally vertical fluid passages 314, a
pair of tubing assemblies 316, a tubing connector assembly 318, a
fluid injection port 320 and a fluid injection fitting 322.
Fluid passages 314 each extend generally vertical from thrust
bearing surface 54 to the internal suction area of shell 12. Each
fluid passage 314 comprises counter bored portion 124 which opens
upon on thrust bearing surface 54. Counter bore portions 124
maintain communication with their respective injection hole 112
during all movement of orbiting scroll member 56. The lower ends of
fluid passages 314 each define an enlarged bore 324 which mates
with a respective tubing assembly 316.
Each tubing assembly 316 extends between tubing connector assembly
318 and a respective enlarged bore 324. Each tubing assembly 316
includes a fitting 326 which engages a respective bore 324 and a
tube 328 which extends between fitting 326 and tubing connector
assembly 318. A seal 330 seals the interface between bore 324 and
fitting 326, and a retainer 332 keeps fitting 326 disposed within
bore 324.
Tubing connector assembly 318 comprises a main bearing housing
fitting 340 and a connecting tube 342. Fitting 340 is secured to
main bearing housing 24 by a plurality of bolts. Fitting 340
defines an internal bore 344 which is in communication with the
pair of tubes 328. Connecting tube 342 is disposed within bore 344
of fitting and extends to fluid injection fitting 322. A seal 346
seals the interface between tube 342 and bore 344.
Fluid injection fitting 322 extends through port 320 and is secured
to shell 12 and it defines an internal bore 350 which receives the
opposite end of connecting tube 342. A seal 352 seals the interface
between tube 342 and bore 350. Thus, fitting 322 is in
communication with pockets of compressed moving fluid defined by
wraps 60 and 72 through bore 350, tube 342, bore 344, tubes 328,
fitting 326, fluid passages 314 and injection passages 112.
Fluid injection system 310 also includes a check valve 360 which
allows fluid flow from fitting 322 to injection passages 112 but
prohibits fluid flow from injection passages 112 to fitting
322.
While the above detailed description describes the preferred
embodiment of the present invention, it should be understood that
the present invention is susceptible to modification, variation and
alteration without deviating from the scope and fair meaning of the
subjoined claims.
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