Information
-
Patent Grant
-
6280155
-
Patent Number
6,280,155
-
Date Filed
Tuesday, March 21, 200024 years ago
-
Date Issued
Tuesday, August 28, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Walberg; Teresa
- Patel; Vinod D
Agents
-
CPC
-
US Classifications
Field of Search
US
- 417 4105
- 417 368
- 418 551
-
International Classifications
-
Abstract
A compressor assembly includes a housing and a compressor mechanism is disposed therein which is partially supported by a manifold. The manifold extends across the interior of the housing, has an aperture therethrough, and subdivides the interior of the housing into a first discharge chamber and a second discharge chamber. An electric motor is disposed in the second discharge chamber and includes a stator and a rotor. A shaft operatively couples the compressor mechanism with the rotor. The manifold includes an aperture into which is received a discharge gas into the first discharge chamber and a plurality of chutes to direct the discharge gas into the second discharge chamber. The chutes are in fluid communication with an exterior of the compressor mechanism defining passages therebetween. The housing includes a main section and an end section which respectively include edges. A bearing support member extends across an interior of the housing and is supported between the edges of the main and end sections of the housing. The bearing support member has portions which project radially outward. An auxiliary bearing is supported by the bearing support member and the auxiliary bearing rotatably supports the shaft. A method of assembly includes: attaching the compressor mechanism to the manifold and welding the manifold to the housing; attaching the stator to the housing and the auxiliary bearing to the bearing support member; aligning the main bearing with the stator and welding the bearing support member to the housing.
Description
BACKGROUND OF THE INVENTION
The present invention relates generally to hermetic compressors for use in cooling, refrigeration or air-conditioning systems, and more particularly to hermetic scroll compressors.
Well known to those having skill in the art are hermetic scroll compressors such as compressor
10
of
FIG. 1
, having a closed hermetic housing
12
comprised of cylindrical section
14
with end cap
16
welded at the upper end thereof and base
18
at the lower end thereof. Base
18
includes a plurality of mounting feet
20
. Compressor
10
has electric motor
22
, which comprises stator
24
fixed inside cylindrical section
14
by, for example, shrink-fitting. Surrounded by stator
24
is rotor
26
, which is attached to shaft
28
by, for example, press-fit. Counterweight
27
is attached to an upper end of shaft
28
and counterweight
31
is attached to rotor
26
, as is customary, to provide substantially balanced rotation of shaft
28
. Shaft
28
is coupled to orbiting scroll
30
through eccentric
29
. Shaft
28
is supported, at opposing ends thereof, by bushing
32
and auxiliary bearing
34
. Bushing
32
is fixed within main bearing
48
by, for example, press-fit. Main bearing
48
and auxiliary bearing
34
are rigidly affixed to an internal surface
33
of cylindrical section
14
of housing
12
typically by press-fit or spot weld methods. Generally, auxiliary bearing
34
includes a plurality of outwardly extended legs
36
secured to internal surface
33
of cylindrical section
14
.
Those having skill in the art of compressor construction readily appreciate that spot welding, although a preferable manufacturing process to attach the bearings to the housing, may cause heat generated distortion which can lead to misalignment of stator-rotor air gap
38
. To facilitate this process, radially directed holes
40
are provided in an end portion of each leg
36
to accommodate a steel pin
42
in each hole. This process further requires each pin
42
to be aligned with each corresponding hole
44
provided in a lower part of cylindrical section
14
. Finally, each pin
42
is spot welded to cylindrical housing section
14
at hole
44
.
Turning now to the construction of the scroll compressor mechanism
57
, in the upper part of housing
12
, is non-orbiting scroll member
46
axially fixed to main bearing
48
by a plurality of bolts
50
in such a manner that orbiting wrap
52
, integral with orbiting scroll member
30
, and non-orbiting wrap
54
, integral with non-orbiting scroll member
46
, combine to form compression cavities or chambers
56
. Orbiting scroll member
30
, non-orbiting scroll member
46
and main bearing
48
comprise compressor mechanism
57
which is positioned in an upper part of cylindrical housing section
14
. A typical procedure associated with assembly of compressor
10
includes request for concentricity of inner radial surface
59
of stator
24
respective of inner radial surface
61
of main bearing
48
. Annular bushing
32
attached to main bearing
48
, by typical means such as press-fit, is substantially concentric with main bearing
48
. Main bearing
48
and bushing
32
must also properly align shaft
28
to provide suitable clearance between orbiting and non-orbiting wraps
52
and
54
, respectively, so proper compression in compression chambers
56
may be attained. After alignment is achieved, main bearing
48
and/or non-orbiting scroll member
46
is welded to housing
12
.
Discharge gas compressed by compressor mechanism
57
flows through discharge port
64
provided with check valve
62
, and into first discharge chamber
66
. First discharge chamber
66
is defined in part by a volume formed between planar surface
68
of non-orbiting scroll
46
and end cap
16
. Thereafter, the discharge gas flows from first discharge chamber
66
to second discharge chamber
70
and exits through discharge tube
72
. Discharge chamber
70
is defined by axial surface
78
of compressor mechanism
57
, internal surface
33
of a portion of housing
14
, generally below compressor mechanism
57
, and external surface
55
of the compressor motor
22
. Discharge chambers
66
and
70
are in fluid communication through narrow (e.g., 0.035″-0.040″wide) passage
74
formed by internal surface
33
of cylindrical section
14
and peripheral surface
69
of compressor mechanism
57
. Discharge tube
72
extends through the wall of cylindrical section
14
of housing
12
and into chamber
70
to transfer refrigerant gas away from compressor assembly
10
.
A problem associated with scroll compressors heretofore, is one of excessive noise caused by refrigerant gas turbulently flowing over the compressor mechanism prior to being discharged from the compressor housing. Compressed refrigerant gas exiting discharge port
64
enters first discharge chamber
66
, and is thereafter forced over peripheral surface
69
of compressor mechanism
57
and into second discharge chamber
70
. Narrow passage
74
, disposed between first discharge chamber
66
and second discharge chamber
70
, is substantially flow-restrictive and consists of a thin ring or annular shaped passage between cylindrical section
14
of housing
12
and compressor mechanism
57
. An outer profile of compressor mechanism
57
, exposed to the refrigerant gas flowing thereover, is generally cylindrical, and includes a pair of axially opposed and generally planar surfaces
76
,
78
, respectively, which are connected by cylindrical surface
80
. The transition of discharge gas flow from axial planar surfaces
76
,
78
, respectively to cylindrical surface
80
generally includes moderately sharp edges which generate turbulence when refrigerant gas flows over compressor mechanism
57
. An increase in noise is attributable to an increase in energy of the gas as gas molecules transition from a substantially ordered state to a substantially unorganized and chaotic state. The noise is transmitted through housing
12
of compressor assembly
10
and into the surrounding area.
Another problem associated with compressor assembly
10
arises during operation wherein localized heating occurs between the rotating rotor
26
and the stationary stator
24
. Region
25
, positioned extending radially through outer peripheral margins of rotor
26
and inner peripheral margins of stator
24
, becomes heated which detrimentally affects motor efficiency.
Yet another problem associated with scroll compressors heretofore, is the costly and laborious procedure of aligning the main bearing, auxiliary bearing and stator within the housing to preserve proper scroll wrap and shaft bearing clearances; typically the clearances required are a few ten thousandths of an inch. This procedure is often referred to as “mounting” the compressor.
Mounting of scroll compressors typically requires the diameter of the cylindrical part of the housing to be machined to provide a reference location to concentrically align the main bearing with the auxiliary bearing and to eliminate uneven stator-rotor gap during assembly. Aligning each bearing relative to the housing requires the bearing support structures to include an outer diameter smaller than that of the inner diameter of the cylindrical section of the housing so that a gap is formed between the structure and the inner surface of the housing. The gap must be uniform and somewhat small to facilitate favorable conditions for alignment and spot welding. Further, as mentioned above, typical scroll compressor design mandates precise radial placement of each bearing, thus, a typical scroll compressor exhibits a supporting bearing structure larger than necessary and/or a plurality of special arms attached to the bearing support to allow for radial adjustability. Unfortunately, these design requirements add to the weight of the compressor, complicate assembly and further add to machining time, which in turn, increases the per unit cost to the manufacturer.
Once the bearings and scroll are suitably aligned, the problem of weldability between metals of dissimilar thicknesses and materials must be addressed. For example, welding the relatively thin compressor housing material to the thick bearing support structures often leads to improper joining and/or distortion. Further, often the bearing structures are steel castings, as is the compressor mechanism, while the housing may be formed from cold rolled steel. Those having skill in the art of welding will appreciate that joining by welding depends upon many correlating factors, such as the shape and size of the weld area, material preheat conditions and the speed at which the joined components heat and cool. Distortion of components leads to a complete loss of all materials and labor to that point, often referred to as “scrap”, and may be caused by excessive stresses in joined components due to unequal cooling or heating during the welding process. Such undesirable distortion not only resides at the weld location, it also migrates throughout the compressor affecting, for example, precision tolerances such as the bearing gaps, wrap clearances, and the stator-rotor gap.
Therefore, a compressor design which preserves the dimensional tolerances necessary for proper operation of the scroll compressor, which are extremely close, generally on the order of a few ten thousandths of an inch, is highly desirable. Additionally, a design which addresses the difficulties associated with unwanted distortion and stressing of the main bearing, bearing structure, compression mechanism and auxiliary bearing caused by press-fit, shrink-fit and welding is most desirable.
Further, an invention which addresses operational noise, due to discharge gas turbulence internal to the housing, by decreasing the noise without adding significant complexity and cost to the compressor assembly, is highly desirable.
SUMMARY OF THE INVENTION
The present invention overcomes the disadvantages associated with prior compressor assemblies in that it provides a compressor assembly including a housing and a manifold which extends across an interior of the housing subdividing the housing into first and second discharge chambers. The first and second discharge chambers are in fluid communication through the manifold. A compressor mechanism is disposed in the housing and into which a fluid is received substantially at suction pressure and from which the fluid is discharged into the first discharge chamber substantially at discharge pressure. The compressor mechanism is attached to the manifold, whereby the compression mechanism is at least partially supported within the housing. An electric motor including a stator and a rotor is disposed in the second discharge chamber and a shaft operatively couples the rotor with the compressor mechanism.
The present invention further provides a compressor assembly including a housing and a compressor mechanism drivingly coupled to an electric motor by means of a shaft. The compressor mechanism and motor are disposed within the housing and the compressor mechanism receives a fluid substantially at suction pressure. A manifold is attached to the housing and subdivides an interior of the housing into first and second discharge chambers. The manifold has an aperture into which is received a discharge gas discharged from the compressor mechanism and the manifold includes a plurality of chutes which receive the discharge gas from the first discharge chamber and thereafter direct the discharge gas into the second discharge chamber.
The present invention further provides a compressor assembly including a housing having a main section and an end section. The main and end sections of the housing include edges. A bearing support member extends across an interior of the housing, is supported between the edges of the main and end sections of the housing and includes portions projecting radially outward to support the compressor assembly. A compressor mechanism is disposed in the housing and includes means for compressing the fluid from substantially suction pressure to substantially discharge pressure. An electric motor including a stator and a rotor are disposed in the housing. A shaft extends through the rotor and operatively couples the rotor and the compressor mechanism. An auxiliary bearing is disposed about the shaft and supported by the bearing support member. The shaft is rotatably supported by the auxiliary bearing.
The present invention further provides a method of assembling a scroll compressor including the steps of: assembling a main bearing, an orbiting scroll and a non-orbiting scroll to form a compressor mechanism; providing a manifold having a planar surface disposed thereon; fastening the compressor mechanism to the planar surface of the manifold to provide perpendicularity of the planar surface respective of a longitudinal axis through a centerline of the main bearing; providing a main section of the housing having first and second planar edges respectively disposed on axial ends thereof such that corresponding surfaces of first and second planar edges are substantially perpendicular to the longitudinal reference axis passing through the centerline of the housing; attaching a stator to the main section of the housing and aligning the stator therewith such that a centerline of an inner radial surface thereof is substantially aligned with the longitudinal centerline of the main section of the housing; inserting the compressor mechanism into the main section such that the planar surface of the manifold faces the stator and abuts the first planar edge of the main section of the housing; aligning the main bearing with the stator such that a centerline of an inner radial surface of the main bearing is aligned with the centerline of the inner radial surface of the stator; joining the planar surface of the manifold to the first planar edge of the main section; providing a bearing support member having a planar surface disposed thereon; fastening the auxiliary bearing to the bearing support member such that a centerline of an inner radial surface of the auxiliary bearing is substantially perpendicular respective of the planar surface of the bearing support member; providing a rotor coupled to a shaft and disposed within the main section of housing such that the longitudinal axis of the shaft and rotor are substantially coaxially positioned respective of the stator; connecting the auxiliary bearing on an end of the shaft; aligning the rotor within the stator such that the rotor and stator are separated by a substantially uniform and annular gap; joining the planar surface of the bearing support member to the second planar edge of the main section of the housing; and joining a pair of end sections to the housing such that one of the pair of end sections is joined to the housing proximate the first planar edge and the other end section is joined to the second planar edge of the main section of the housing.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of an embodiment of the invention taken in conjunction wit the accompanying drawings, wherein:
FIG. 1
is a longitudinal sectional view of a prior art compressor assembly;
FIG. 2
is a longitudinal sectional view of the compressor assembly according to the present invention;
FIG. 3
is a longitudinal sectional view of the compressor assembly of
FIG. 2
sectioned through a centerline of the manifold chutes;
FIG. 4A
is a top view of the manifold;
FIG. 4B
is a sectional view along line
4
B—
4
B of
FIG. 4A
;
FIG. 4C
is a sectional view along line
4
C—
4
C of
FIG. 4A
;
FIG. 5
is a perspective view of the manifold;
FIG. 6A
is a top view of a fixed scroll;
FIG. 6B
is a sectional view along line
6
B—
6
B of
FIG. 6A
;
FIG. 7
is an enlarged fragmentary view of the compressor assembly shown in
FIG. 3
, showing the scroll compressor mechanism and the manifold;
FIG. 8
is a fragmentary perspective view of the compressor assembly shown in
FIG. 7
with a portion thereof broken away;
FIG. 9A
is a transverse view of the bearing support member;
FIG. 9B
is a sectional view along line
9
B—
9
B of
FIG. 9A
; and
FIG. 9C
is a sectional view along line
9
C—
9
C of FIG.
9
A.
Corresponding reference characters indicate corresponding parts throughout the several views. Although the drawings represent an embodiment of the present invention, the drawings are not necessarily to scale and certain features may be exaggerated in order to better illustrate and explain the present invention. The exemplification set out herein illustrates an embodiment of the invention in one form thereof, and such exemplification is not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
The present invention overcomes the disadvantages of the above described prior art scroll compressors by providing an improved compressor mounting arrangement requiring fewer components, resulting in less manufacturing time and less assembly required which corresponds to a substantial cost savings. The present invention also provides both a quieter and cooler operating compressor.
Referring to
FIGS. 2 and 3
, compressor assembly
82
of the present invention is shown, and in contrast to the prior art compressor shown in
FIG. 1
, discloses a noise attenuating manifold and a bearing support structure which are illustrated respectively by manifold
84
and bearing support member
86
. Compressor assembly
82
includes closed hermetic housing
88
comprised of main section
90
welded to manifold
84
and having first end section
92
enclosing an upper portion of compressor housing
88
by being welded thereto. In a lower portion of housing
88
is bearing support member
86
, which is generally disc-shaped and welded to a lower portion of main section
90
of housing
88
to support auxiliary bearing
94
fastened thereto. Second end section
96
of housing
88
, equal in size to the first end section
92
, is welded to bearing support member
86
to hermetically enclose housing
88
and provide an oil sump
97
. Lower portion
95
of auxiliary bearing
94
extends through bearing support member
86
and into sump
97
. Oil pump
103
, disposed within lower portion
95
of auxiliary bearing
94
, forces oil, pooled within sump
97
, through shaft
106
to lubricate compressor mechanism
120
in a well known manner. Formed as a unitary piece is bearing support member
86
including a projecting outer periphery portion comprising a plurality of mounting feet
98
to support compressor assembly
82
(
FIGS. 2
,
3
and
9
B). Hermetic housing
88
is subdivided into two distinct portions by bearing support member
86
. First housing portion
99
is disposed above bearing support member
86
and includes motor
100
and compressor mechanism
120
provided therein. Second housing portion
101
is disposed below bearing support member
86
and includes feet
98
of bearing support member
86
. Second end section
96
of housing
88
is joined to bearing support member
86
by, for example, welding to form sump
97
which is located generally above second housing portion
101
and below bearing support member
86
.
Within main section
90
of housing
88
is electric motor
100
which comprises stator
102
connected to main section
90
by, for example, shrink-fit. Rotor
104
is attached to shaft
106
by press-fit or other like connecting method. At an upper end of compressor assembly
82
, shaft
106
drives orbiting scroll
108
through eccentric
109
as is customary. Shaft
106
is supported by main bearing
112
, through bushing
110
. Counterweight
105
is attached to an upper end of shaft
106
and counterweight
107
is attached to rotor
104
, as is customary, to provide substantially balanced rotation of shaft
106
. Rotation of shaft
106
is transformed into non-rotating translation of orbiting scroll
108
through known means such as an Oldham coupling. At a lower end of compressor assembly
82
, below motor
100
, shaft
106
is supported by outboard or auxiliary bearing
94
. Annular bushing
110
is connected by press fit with inner radial surface
111
of main bearing
112
to support shaft
106
. Non-orbiting scroll
118
is secured between main bearing
112
and manifold
84
by screws
114
(FIG.
2
). Auxiliary bearing
94
is fastened to bearing support member
86
by screws
116
. Non-orbiting scroll
118
, orbiting scroll
108
and main bearing
112
form compressor mechanism
120
.
Referring to
FIGS. 2
,
3
and
7
, in operation, electric motor
100
drives compressor mechanism
120
to compress refrigerant gas, introduced into inlet port
122
(
FIG. 8
) at suction pressure, within compression chamber
124
. Compression chamber
124
is defined by a plurality of compression cavities
126
positioned between non-orbiting involute wrap element
128
and orbiting involute wrap element
130
. Thus, orbiting involute wrap element
130
, driven by motor
100
, orbits about non-orbiting involute wrap element
128
to compress refrigerant gas therebetween.
Compressed refrigerant gas, at its final compressed state (substantially at discharge pressure), exits compressor cavities
126
through discharge port
132
(
FIGS. 2
,
3
,
6
A,
6
B,
7
and
8
) then flows into first discharge chamber
134
through check valve
136
. Check valve
136
prevents compressed refrigerant from reversing or flowing back into port
132
from first discharge chamber
134
to help prevent reverse orbiting of the orbiting scroll. Refrigerant gas flows from first discharge chamber
134
to second discharge chamber
138
through four radial projecting semi-circular chutes
146
disposed within manifold
84
. Four jets of discharge gas, in fluid communication with chutes
146
, are directed through passages
158
(FIGS.
7
and
8
). Notably, and as best seen in
FIGS. 7 and 8
, annular gap
140
, a thin ring defined by an interior wall of housing
88
and the exterior peripheral surface of compressor mechanism
120
, is otherwise flow restrictive when refrigerant gas is discharged from first discharge chamber
134
to second discharge chamber
138
, however, compressor mechanism
120
includes channels
162
to accommodate increased flow. Compressor assembly
82
includes four channels
162
, formed in surface
151
of non-orbiting scroll
118
in compressor mechanism
120
, positioned adjacent annular gap
140
(FIG.
2
). Channels
162
decrease the axial length of annular gap
140
, along the exterior of compressor mechanism
120
which increases the flow of discharge gas otherwise restricted by substantially cylindrical compressor mechanism
120
.
Referring to
FIGS. 2 and 3
, compressor assembly
82
includes discharge manifold
84
attached to compressor mechanism
120
and welded to main section
90
of housing
88
. Main bearing
112
includes bushing
110
fitted therein to receive rotating drive shaft
106
and main bearing
112
is attached by way of screws
114
(
FIG. 7
) to non-orbiting scroll
118
. Nonorbiting scroll
118
includes discharge port
132
(
FIGS. 6A and 6B
) therein to provide an exit for compressed refrigerant gas to exit compressor mechanism
120
. Refrigerant gas, contained within first discharge chamber
134
, is transferred to second discharge chamber
138
by flowing over an exterior of compressor mechanism
120
. Typical compressor mechanisms are “cylinder-shaped” (
FIG. 1
) and in contrast, compressor mechanism
120
includes four equidistantly arranged channels
162
forming generally round-edged axial cross-section
121
(FIG.
3
). The channels
162
are positioned adjacent the four discharge chutes
146
disposed on manifold
84
, to promote an increased boundary layer of refrigerant gas flow between each channel
162
and respective chute
146
. The refrigerant gas then flows into second discharge chamber
138
and exits housing
88
through discharge pipe
142
(FIGS.
2
and
3
).
Referring to
FIGS. 4A-4C
and
5
, manifold or muffler plate
84
may be integrally formed by, for example, cold forming a steel plate through a stamping process, to form an annular, one piece unit which serves as a muffler to attenuate noise created by discharge gas. Additionally, manifold
84
serves as a structure to support the compressor mechanism. Manifold
84
is generally a disc shaped member having a generally circular base portion
144
. Manifold
84
includes four semi-circular chutes
146
, extending radially and arranged symmetrically about, and equidistantly from, the center of base portion
144
. However, it is envisioned that an asymmetrical arrangement of chutes
146
would also provide suitable noise attenuation. Non-orbiting scroll
118
is secured to manifold
84
by screws
114
which extend through holes
148
in manifold
84
and thread into non-orbiting scroll
118
(
FIGS. 2
,
3
and
7
).
Referring to
FIGS. 2
,
7
and
8
, which best show the manifold's attachment to housing
88
, manifold
84
includes base
144
having machined surface
150
, defining a reference surface which is substantially perpendicular to a centerline of radial inner surface
149
of bushing
110
, which is substantially concentric with a radial inner surface of main bearing
112
. Surface
150
is adapted to abuttingly contact correspondingly machined annular top edge
152
of housing
88
. Surface
150
also defines a plane which is substantially perpendicular to a centerline axis of inner radial surface
154
of stator
102
within main section
90
of housing
88
(FIGS.
2
and
3
). Surface
150
of manifold
84
is welded to annular top edge
152
of housing
88
. Stator
102
is fixed to housing
88
by way of, for example, shrink-fitting. Holes
156
(
FIGS. 4A-4C
and
5
) in manifold
84
provide oil passages between first discharge chamber
134
and sump
97
to allow oil accumulated in first discharge chamber
134
to be reclaimed by oil sump
97
(FIGS.
2
and
3
).
Referring to
FIGS. 6A
,
6
B,
7
and
8
, further describing the operation of manifold
84
and compressor mechanism
57
, compressed refrigerant gas is discharged from discharge port
132
and into first discharge chamber
134
through check valve
136
(not shown in FIG.
8
). The gas then flows through a first portion of four passages
158
(FIGS.
7
and
8
), each formed by inner wall surface
160
of each chute
146
and respective surface
164
of each channel
162
within non-orbiting scroll
118
(
FIGS. 6A
,
6
B and
7
). Surface
164
of each channel
162
follows a generally semi-circular exterior profile of non-orbiting scroll
118
and provides a generally smooth and unobtrusive path for the refrigerant gas to flow from first discharge chamber
134
to a second portion of passages
158
. A second portion of passages
158
abut channels
162
in non-orbiting scroll
118
and are formed in main bearing
112
. Four equidistantly arranged channels
168
having respective surfaces
166
are disposed within exterior surface portions of main bearing
112
. Each channel
168
, provided in main bearing
112
, abuts channel
162
, in non-orbiting scroll
118
, such that channel
162
continuously extends into channel
168
. Refrigerant gas is directed from first discharge chamber
134
to second discharge chamber
138
through passages
158
by remaining attached, as a gas layer having a boundary, to channels
162
,
168
, and inner wall surfaces
160
of chutes
146
. This attachment of gas, known to those having skill in the art as a “Coanda effect”, involves attachment of high velocity fluid to a surface. As best seen in
FIGS. 3 and 7
, passages
158
are continuous along exterior portions of the generally oval cross-section of compressor mechanism
120
(FIG.
3
). Further, the refrigerant gas remains attached, under a Coanda effect from surface
164
of fixed scroll
118
to surface
166
of main bearing
112
and is thereafter directed to electric motor
100
. Flow of refrigerant gas directed to motor
100
decreases heat generated in windings and increases performance of the compressor assembly
82
.
Referring to
FIGS. 3
,
7
and
8
, noise attenuation, associated with fluid flow through compressor assembly
82
, is achieved by the discharge gas being directed through multiple passages
158
. A single jet of discharge gas, exiting discharge port
132
of non-orbiting scroll
118
, has associated therewith a particular energy level, a portion of which manifests itself in the form of audible noise. This energy level, and associated noise, may be reduced by segmenting and segregating the single jet into multiple smaller jets which imparts a significant energy loss on the aggregate discharge flow. Additionally, discharge flow noise may be further decreased by directing discharge gas flow over generally curved and gradually sloped walls defining arcuate passages, e.g., the inner wall surfaces
160
of chutes
146
and surfaces
164
,
166
of respective channels
162
,
168
defining flow passages
158
, to prolong the boundary layer attachment of discharge gas flow to aforesaid surfaces. Increasing boundary layer attachment acts to further diminish the noise associated with flow turbulence.
Compressor assembly
82
includes motor
100
comprised of rotational rotor
104
and stationary stator
102
separated by rotor-stator air gap
186
. Heat generated from friction and current flow through motor windings adversely affects motor performance. The generated heat is reduced by utilizing the Coanda effect, i.e., discharge gas attached to surface
166
of compressor mechanism
120
disattaches and is directed toward motor
100
to cool the motor windings. This cooling effect increases motor efficiency and increases performance of the compressor.
Turning now to the mounting structure of the present invention, as best seen in
FIGS. 2 and 3
, compressor assembly
82
includes auxiliary bearing
94
mounted in a lower part of housing
88
. Auxiliary bearing
94
is fastened to bearing support member
86
and bearing support member
86
is attached to housing
88
. Bearing support member
86
has a plurality of mounting feet
98
integrally formed by, for example, a cold forming process such as stamping, which support compressor assembly
82
in a generally upright or vertical position. As best seen with reference to
FIGS. 3 and 9A
, bearing support member
86
has clearance hole
174
to accommodate a lower portion
176
of auxiliary bearing
94
. Four holes
178
in bearing support member
86
align with corresponding threaded holes
180
in bearing
94
to receive screws
116
therein to fasten auxiliary bearing
94
to bearing support member
86
. Auxiliary bearing
94
has a plurality of arcuate apertures
184
which are aligned with the rotor-stator air gap
186
of motor
100
to provide adjustability of gap
186
through clearance hole
174
in bearing support member
86
following assembly of compressor mechanism
120
with main section
90
of housing
88
(FIGS.
2
and
3
). A portion of oil transferred with the discharge gas, otherwise accumulating on bearing support member
86
, is transferred to sump
97
through apertures
188
in bearing support member
86
(
FIGS. 2
,
3
and
9
A). Also, oil dispersed within refrigerant gas, which may accumulate within rotor-stator air gap
186
, is reclaimed by oil sump
97
through arcuate apertures
184
in auxiliary bearing
94
.
Referring to FIGS.
3
and
9
A-
9
C, bearing support member
86
includes surface
192
which has peripheral shoulder portion
194
adapted to abut edge surface
196
of main section
90
of housing
88
. Edge surface
196
is machined and abuts shoulder portion
194
of surface
192
of bearing support member
86
such that edge surface
196
is substantially perpendicular to a centerline axis of inner radial surface
154
of stator
102
(FIGS.
2
and
3
).
Referring to
FIG. 3
, a method of assembly of compressor assembly
82
which minimizes distortion of the main bearing, auxiliary bearing and scroll wraps, during heating and cooling processes associated with welding will be discussed. The process of assembly of compressor assembly
82
includes the steps of: assembling main bearing
112
(after press fit of bushing
110
therein), orbiting scroll
108
and non-orbiting scroll
118
to form compressor mechanism
120
; machining planar surface
150
of manifold
84
to establish perpendicularity of a reference plane disposed on surface
150
to an axial centerline of main bearing
112
whereby planar surface
150
is used as the reference for locating rotor
104
vertically; fastening manifold
84
to top portion
151
of compressor mechanism
120
; machining end surfaces
152
,
196
respectively of main section
90
of housing
88
to provide substantially parallel surfaces with respect to each other and substantially perpendicular to an axis passing through the centerline of inner radial surface of stator
154
; shrink-fitting stator
102
into main section
90
of housing
88
whereby a first planar edge
152
of main section
90
provides a reference for locating stator
102
vertically; inserting compressor mechanism
120
into housing such that surface
150
of manifold
84
, facing stator
102
, abuts the corresponding first planar edge
152
of main section
90
; inserting a mandrel, or dummy rotor, into a cavity of stator
102
to concentrically align main bearing
112
with stator
102
; spot welding manifold
84
to main housing section
90
; machining peripheral surface
192
of bearing support member
86
to provide substantial perpendicularity between peripheral surface
192
and a centerline axis with respect to an inner radial surface
198
of auxiliary bearing
94
; fastening auxiliary bearing
94
to bearing support member
86
; inserting a shaft
106
coupled to a rotor
104
into the stator
102
and fitting the auxiliary bearing
94
onto an end of the shaft until planar surface of bearing support member
86
abuts second planar edge of main section of housing; inserting gages into apertures
184
within auxiliary bearing
94
to set gap
186
between stator
102
and rotor
104
; providing a continuous weld to join bearing support member
86
with main section
90
of housing
88
; and welding end sections
92
,
96
to each respective end
152
,
86
of housing
88
to sealably enclose housing
88
.
While this invention has been described as having an exemplary embodiment, the present invention may be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. For example, aspects of the present invention may be applied to rotary compressors. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains.
Claims
- 1. A compressor assembly comprising:a housing; a manifold having an aperture therethrough, said manifold extending across an interior of said housing subdividing said housing into first and second discharge chambers, said first and second discharge chambers in fluid communication through said aperture in said manifold; a compressor mechanism disposed in said housing and into which a fluid is received substantially at suction pressure and from which the fluid is discharged into said first discharge chamber substantially at discharge pressure, said compressor mechanism attached to said manifold, whereby said compression mechanism is at least partially supported within said housing by said manifold; an electric motor comprising a stator and a rotor disposed in said second discharge chamber; and a shaft operatively coupling said rotor and said compressor mechanism.
- 2. The compressor assembly of claim 1, wherein said manifold constitutes a muffler.
- 3. The compressor assembly of claim 1, wherein said compressor mechanism comprises a fixed scroll member attached to said manifold and having a fixed involute wrap element projecting from a substantially planar surface thereof, and an orbiting scroll member operatively coupled to said shaft and having an orbiting involute wrap element projecting from a substantially planar surface thereof, said fixed and orbiting scroll members mutually engaged with said fixed involute wrap element projecting towards said substantially planar surface of said orbiting scroll member, and said orbiting involute wrap element projecting towards said substantially planar surface of said fixed scroll member, said substantially planar surfaces positioned substantially parallel with one another, whereby relative orbiting of said scroll members compresses the fluid between said involute wrap elements, said fixed scroll member having a discharge port which extends from a space between said involute wrap elements to said first discharge chamber.
- 4. The compressor assembly of claim 1, wherein said aperture is substantially centrally located in said manifold.
- 5. The compressor assembly of claim 1, wherein the fluid is discharged from said compressor mechanism through said manifold aperture.
- 6. The compressor assembly of claim 5, wherein said manifold is provided with a plurality of projections distributed about said aperture, said projections partially defining a plurality of chutes through which said first and second discharge chambers are in fluid communication.
- 7. The compressor assembly of claim 6, wherein said plurality of projections extend into said first discharge chamber.
- 8. The compressor assembly of claim 7, wherein said plurality of projections are radially and equidistantly distributed about said aperture.
- 9. The compressor assembly of claim 7, wherein said manifold directs the fluid which is received into said second discharge chamber from said first discharge chamber toward said stator.
- 10. The compressor assembly of claim 7, wherein said compressor mechanism includes a plurality of channels disposed on a periphery of said compressor mechanism, said first and second discharge chambers are in fluid communication through said plurality of channels.
- 11. The compressor assembly of claim 10, wherein each said plurality of projections include an inner surface and each said plurality of channels defines a surface, each inner surface of said projection and respective said surface of said channel define a passage to receive the discharge gas.
- 12. The compressor assembly of claim 11, wherein the fluid received into said second discharge chamber from said first discharge chamber is directed along said plurality of channels and towards said stator under the influence of a Coanda effect.
- 13. The compressor assembly of claim 12, wherein said compressor mechanism constitutes a scroll compressor including a fixed scroll mounted to a main bearing, each said plurality of channels is continuous and defined by a sub-channel formed within a radially exterior surface of said fixed scroll and contiguous with a sub-channel formed within an exterior surface of said main bearing.
- 14. The compressor assembly of claim 1, further comprising means for subdividing the flow of the fluid substantially at discharge pressure which is received into said first discharge chamber into a plurality of jets.
- 15. The compressor assembly of claim 14, wherein said means for subdividing the flow further comprises means for minimizing the turbulence of the flow of the fluid substantially at discharge pressure which is received into said first discharge chamber, whereby the noise associated with the flow of fluid substantially at discharge pressure is reduced.
- 16. A compressor assembly comprising:a housing; a compressor mechanism drivingly coupled to an electric motor by means of a shaft, said compressor mechanism and motor disposed within said housing and said compressor mechanism receiving a fluid substantially at suction pressure; and a manifold attached to said housing and subdividing an interior of said housing into first and second discharge chambers, said manifold having an aperture into which is received a discharge gas discharged from said compressor mechanism disposed within said second discharge chamber, said manifold including a plurality of chutes; said compressor mechanism including a plurality of channels disposed on a peripheral surface and each channel positioned adjacent the respective chute, each said channel defining a generally arcuate profile extending between a pair of substantially planar axial end surfaces defining said compressor mechanism.
- 17. The compressor assembly of claim 16, wherein each said chute in said manifold includes an inner surface and each said channel in said peripheral surface of said compressor mechanism defines a surface, each said inner surface of said chute and respective said surface of said channel defines a passage.
- 18. The compressor assembly of claim 16, wherein one of said pair of axial end surfaces of said compressor mechanism includes a discharge port and is attached to said manifold, said shaft extending axially and outwardly from the other said axial end surface.
- 19. The compressor assembly of claim 16, wherein said compressor mechanism constitutes a scroll compressor having a fixed scroll, a main bearing and an orbiting scroll, said peripheral surface being defined by exterior portions of said main bearing and said fixed scroll, fluid received into said second discharge chamber from said first discharge chamber is directed along said peripheral surface under the influence of a Coanda effect.
- 20. The compressor assembly of claim 19, wherein fluid is further directed from said peripheral surface of said compressor mechanism to said electric motor under the influence of a Coanda effect, whereby heat generated by said motor is decreased.
- 21. A compressor assembly comprising:a housing comprising a main section and an end section, said main and end sections of said housing including edges; a bearing support member extending across an interior of said housing and supported between said edges of said main and end sections of said housing, said bearing support member having portions projecting radially outward to support the compressor assembly; a compression mechanism disposed in said housing and comprising means for compressing the fluid from substantially suction pressure to substantially discharge pressure; an electric motor comprising a stator and a rotor disposed in said housing, an air gap is disposed between said stator and rotor; a shaft extending through said rotor and operatively coupling said rotor and said compressor mechanism; and an auxiliary bearing disposed about said shaft and supported by said bearing support member, said shaft rotatably supported by said auxiliary bearing.
- 22. The compressor assembly of claim 21, wherein said shaft is vertically positioned and said bearing support member includes radially outward portions which extend to the exterior of said housing and define a plurality of feet, said compressor assembly supported by said feet.
- 23. The compressor assembly of claim 21, wherein said bearing support member is substantially disc-shaped.
- 24. The compressor assembly of claim 22, wherein said bearing support member is provided with a clearance hole, said auxiliary bearing extending through said clearance hole.
- 25. The compressor assembly of claim 24, further comprising an oil sump at least partially defined by the interior of said housing, said auxiliary bearing at least partially located in said oil sump.
- 26. The compressor assembly of claim 25, wherein said bearing support member is located above said oil sump.
- 27. The compressor assembly of claim 25, wherein said bearing support member includes a planar portion substantially extended radially across said housing whereby said planar portion prevents oil in said sump from being suctioned into said air gap.
- 28. The compressor assembly of claim 22, wherein said oil sump is located above said second housing portion.
- 29. The compressor assembly of claim 22, further comprising an oil pump disposed in said sump and located within said auxiliary bearing.
- 30. The compressor assembly of claim 29, wherein an inlet to said oil pump is located between said bearing support member and said second housing portion.
- 31. The compressor assembly of claim 30, wherein said bearing support member is provided with a plurality of apertures through which oil flows toward said oil pump inlet.
- 32. The compressor assembly of claim 31, wherein said shaft has an axis of rotation and said auxiliary bearing is provided with a plurality of apertures extending therethrough in directions substantially parallel with said shaft axis of rotation, each said aperture aligns with and overlays said air gap between said rotor and said stator, whereby inspection of the width of said gap is facilitated by said apertures.
- 33. The compressor assembly of claim 32, wherein said apertures within said auxiliary bearing align with and overlay said clearance hole in said bearing support member, whereby oil dispensed within the discharge gas and disposed within said rotor-stator air gap is directed to said oil sump through said apertures within said auxiliary bearing and through said clearance hole.
- 34. A method of assembling a scroll compressor comprising the steps of:assembling a main bearing, an orbiting scroll and a non-orbiting scroll to form a compressor mechanism; providing a manifold having a planar surface disposed thereon; fastening the compressor mechanism to the planar surface of the manifold to provide perpendicularity of the planar surface respective of a longitudinal axis through a centerline of the main bearing; providing a main section of the housing having first and second planar edges respectively disposed on axial ends thereof such that corresponding surfaces of first and second planar edges are substantially perpendicular to a longitudinal reference axis passing through the centerline of the housing; attaching a stator to the main section of the housing and aligning the stator therewith such that a centerline of an inner radial surface thereof is substantially aligned with the longitudinal centerline of the main section of the housing; inserting the compressor mechanism into the main section such that the planar surface of the manifold faces the stator and abuts the first planar edge of the main section of the housing; aligning the main bearing with the stator such that a centerline of an inner radial surface of the main bearing is aligned with the centerline of the inner radial surface of the stator; joining the planar surface of the manifold to the first planar edge of the main section; providing a bearing support member having a planar surface disposed thereon; fastening the auxiliary bearing to the bearing support member such that a centerline of an inner radial surface of the auxiliary bearing is substantially perpendicular respective of the planar surface of the bearing support member; providing a rotor coupled to a shaft and disposed within the main section of housing such that the longitudinal axis of the shaft and rotor are substantially coaxially positioned respective of the stator; connecting the auxiliary bearing on an end of the shaft; aligning the rotor within the stator such that the rotor and stator are separated by a substantially uniform and annular air gap; joining the planar surface of the bearing support member to the second planar edge of the main section of the housing; and joining a pair of end sections to the housing such that one of the pair of end sections is joined to the housing proximate the first planar edge and the other end section is joined to the second planar edge of the main section of the housing.
US Referenced Citations (35)