U.S. patent application number 12/706913 was filed with the patent office on 2010-08-26 for compressor and refrigerating apparatus having the same.
Invention is credited to Yang-Hee Cho, Se-Heon Choi, Chul-Su Jung, Cheol-Hwan KIM, Byeong-Chul Lee, In-Hon Won.
Application Number | 20100212352 12/706913 |
Document ID | / |
Family ID | 42342495 |
Filed Date | 2010-08-26 |
United States Patent
Application |
20100212352 |
Kind Code |
A1 |
KIM; Cheol-Hwan ; et
al. |
August 26, 2010 |
COMPRESSOR AND REFRIGERATING APPARATUS HAVING THE SAME
Abstract
A scroll compressor and a refrigerating apparatus having the
same are provided. In the scroll compressor, an angle formed
between an injection passage that guides refrigerant from a
condenser back into an intermediate compression chamber and a back
pressure passage that guides refrigerant from the intermediate
compression chamber into a back pressure chamber may be designed so
as to prevent leakage of refrigerant from the intermediate
compression chamber into the back pressure chamber. This allows an
appropriate pressure to be maintained the back pressure chamber,
and increases an amount of refrigerant supplied into the
compression chambers, thereby improving performance of the scroll
compressor and a refrigerating apparatus in which such a scroll
compressor is installed.
Inventors: |
KIM; Cheol-Hwan; (Seoul,
KR) ; Choi; Se-Heon; (Seoul, KR) ; Lee;
Byeong-Chul; (Seoul, KR) ; Cho; Yang-Hee;
(Seoul, KR) ; Jung; Chul-Su; (Seoul, KR) ;
Won; In-Hon; (Seoul, KR) |
Correspondence
Address: |
KED & ASSOCIATES, LLP
P.O. Box 221200
Chantilly
VA
20153-1200
US
|
Family ID: |
42342495 |
Appl. No.: |
12/706913 |
Filed: |
February 17, 2010 |
Current U.S.
Class: |
62/498 ;
418/55.2; 62/513 |
Current CPC
Class: |
F04C 27/005 20130101;
F04C 29/042 20130101; F04C 18/0253 20130101; F04C 18/0215
20130101 |
Class at
Publication: |
62/498 ;
418/55.2; 62/513 |
International
Class: |
F25B 1/00 20060101
F25B001/00; F01C 1/02 20060101 F01C001/02; F25B 41/00 20060101
F25B041/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 25, 2009 |
KR |
10-2009-0015847 |
Claims
1. A scroll compressor, comprising: a casing; a fixed scroll fixed
to an interior of the casing; an orbiting scroll movably engaged
with the fixed scroll so as to form compression chambers
therebetween that are consecutively moved as the orbiting scroll
moves relative to the fixed scroll; a back pressure chamber formed
at a bearing surface formed between the fixed and orbiting scrolls,
wherein the back pressure chamber is configured to support a
position of the orbiting scroll against the fixed scroll; a first
passage formed in one of the fixed scroll or the orbiting scroll
and configured to guide refrigerant compressed in the compression
chambers back into the back pressure chamber; and a second passage
formed at the one of the fixed scroll or the orbiting scroll and
configured to guide refrigerant, which has been discharged from the
compression chambers into a refrigerating cycle, back into the
compression chambers from an intermediate portion of the
refrigerating cycle.
2. The compressor of claim 1, further comprising a main frame fixed
to the interior of the casing so as to support the fixed scroll and
the orbiting scroll.
3. The compressor of claim 2, wherein the back pressure chamber is
defined by a recess formed in an upper surface of the main frame, a
lower surface of the fixed scroll, and an outer peripheral portion
of the orbiting scroll.
4. The compressor of claim 3, further comprising a groove formed in
the lower surface of the fixed scroll so as to provide for
communication between the first passage, which is formed in the
fixed scroll, and the back pressure chamber.
5. The compressor of claim 4, wherein the first passage comprises:
a first bypass hole having a first end connected to the
communication groove; a second bypass hole having a first end
alternately connected to the compression chambers as the orbiting
scroll moves relative to the fixed scroll; and a third bypass hole
that connects second ends of the first and second bypass holes.
6. The compressor of claim 5, further comprising a blocking member
positioned in an external end of the third bypass hole so as to
seal the first passage.
7. The compressor of claim 1, wherein the second passage comprises:
a first injection hole that extends into a plate portion of the
fixed scroll; and a second injection hole having a first end
connected to the first injection hole and a second end that
alternately communicates with the compression chambers.
8. The compressor of claim 7, wherein an inlet end of the first
injection hole is connected to an injection pipe that extends
through an outer wall of the casing so as to receive refrigerant
from an intermediate section of a refrigerating cycle and to direct
the received refrigerant back into the compression chambers through
the second passage.
9. The compressor of claim 1, wherein the first passage is formed
in the fixed scroll and is configured to communicate with one of
the compression chambers at an intermediate pressure between a
suction pressure and a discharge pressure.
10. The compressor of claim 1, wherein the second passage is formed
in the fixed scroll and is configured to with one of the
compression chambers at an intermediate pressure between a suction
pressure and a discharge pressure.
11. The compressor of claim 1, wherein an angle between the first
passage and the second passage is greater than approximately
30.degree..
12. The compressor of claim 11, wherein an outlet of the first
passage is closer to a discharge side of the compression chambers
than an outlet of the second passage is.
13. The compressor of claim 1, wherein a diameter of an outlet of
the second passage is greater than or equal to a diameter of an
outlet of the first passage.
14. A refrigerating apparatus comprising the scroll compressor of
claim 1.
15. A scroll compressor, comprising: a fixed scroll having spiral
fixed wraps formed thereon; an orbiting scroll having spiral
orbiting wraps formed thereon, wherein the spiral orbiting wraps
are engaged with the spiral fixed wraps so as to form a pair of
compression chambers that are consecutively moved as the orbiting
scroll orbits relative to the fixed scroll; a back pressure chamber
formed at an outer peripheral portion of the orbiting scroll,
wherein the back pressure chamber receives bypassed refrigerant
from the pair of compression chambers; a pressure passage formed in
the fixed scroll, wherein the back pressure passage provides for
communication between the pair of compression chambers and the back
pressure chamber; and an injection passage formed in the fixed
scroll, wherein the injection passage receives refrigerant from an
intermediate portion of a refrigerating cycle and injects the
received refrigerant back into the pair of compression
chambers.
16. The compressor of claim 15, wherein the injection passage is
closer to a discharge side of the pair of compression chambers than
the back pressure passage is.
17. The compressor of claim 15, wherein an angle between the back
pressure passage and the injection passage is greater than
approximately 30.degree..
18. The compressor of claim 15, wherein a diameter of the injection
passage is greater than or equal to a diameter of the back pressure
passage.
19. The compressor of claim 18, wherein a diameter of the injection
passage is less than a thickness of the orbiting wraps.
20. A refrigerating apparatus, comprising: a compressor; a
condenser connected to a discharge side of the compressor; an
expansion apparatus connected to the condenser; an evaporator
connected to the expansion apparatus and to a suction side of the
compressor; a valve positioned between the condenser and the
expansion apparatus so as to direct a flow of refrigerant
therethrough; and a bypass pipe connected to the valve and to the
compressor, wherein the valve directs a portion of refrigerant from
the condenser through the bypass pipe and back into the
compressor.
21. The apparatus of claim 20, further comprising a heat exchanger
provided at the bypass pipe, wherein the heat exchanger is
configured to perform a re-heat-exchange process with the
condenser.
22. The apparatus of claim 20, further comprising an injection
passage that connects the bypass pipe to the compressor, wherein
the bypass pipe is closer to a discharge side of a compression
chamber of the compressor than to a back pressure passage of the
compressor.
23. The apparatus of claim 22, wherein an angle formed between the
injection passage and the back pressure passage is greater than
approximately 30.degree..
24. The apparatus of claim 22, wherein a diameter of the injection
passage is greater than or equal to that of the back pressure
passage, and less than a thickness of an orbiting scroll wrap of
the compressor.
Description
BACKGROUND
[0001] 1. Field
[0002] This relates to a compressor and, in particular, to a
compressor including refrigerant bypasses, and a refrigerating
apparatus including such a compressor.
[0003] 2. Background
[0004] A compressor is a component of a refrigerating cycle that
compresses refrigerant gas. Types of compressors may include, for
example, a reciprocating compressor in which a refrigerant is
compressed by a piston and crank shaft, a rotary compressor in
which refrigerant gas is compressed by a rotor and vanes, or a
scroll compressor in which refrigerant gas is compressed in
compression chambers formed by two inter-engaged scrolls, one
rotating relative to the other. The scroll compressor may exhibit
higher efficiency and lower vibration and noise compared to the
reciprocating compressor or the rotary compressor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The embodiments will be described in detail with reference
to the following drawings in which like reference numerals refer to
like elements wherein:
[0006] FIG. 1 is a longitudinal sectional view of an upper portion
of a scroll compressor in accordance with an embodiment as broadly
described herein;
[0007] FIG. 2 is a cut-away view of a compression unit of the
scroll compressor shown in FIG. 1;
[0008] FIG. 3 is a view taken along the line "II-II" of FIG. 2;
[0009] FIG. 4 is an enlarged longitudinal sectional view of a back
pressure passage shown in FIG. 3;
[0010] FIG. 5 is an enlarged longitudinal sectional view of an
injection passage shown in FIG. 3;
[0011] FIG. 6 is a view taken along the line "I-I" of FIG. 2;
[0012] FIG. 7 is an enlarged view of a phase difference between the
back pressure passage and the injection passage shown in FIG.
6;
[0013] FIG. 8 is a schematic view of a refrigerating cycle
including a scroll compressor as embodied and broadly described
herein;
[0014] FIGS. 9A and 9B are graphs of pressure variation inside the
back pressure chamber of the scroll compressor based on the phase
difference between the back pressure passage and the injection
passage in the refrigerating cycle shown in FIG. 8; and
[0015] FIG. 10 is a perspective view of an exemplary air
conditioner having the scroll compressor shown in FIG. 1.
DETAILED DESCRIPTION
[0016] Scroll compressors may be divided into low pressure type
scroll compressors and high pressure type scroll compressors based
on how refrigerant is supplied into its compression chambers. That
is, in a low pressure type scroll compressor, refrigerant may be
indirectly drawn into a compression chamber via an inner space of a
casing, the inner space of the casing being divided into a suction
space and a discharge space. In a high pressure type scroll
compressor, refrigerant may be supplied directly into a compression
chamber without flowing through the inner space of the casing, and
may then be discharged into the inner space of the casing, such
that a majority of the inner space of the casing defines a
discharge space.
[0017] Scroll compressors may also be divided into a tip seal type
scroll compressor and a back pressure type scroll compressor based
on a sealing mechanism used in the compression chamber. That is, in
a tip seal mechanism, a tip chamber disposed at an upper end of
wraps of each scroll is raised so as to be closely adhered to a
plate portion of a facing scroll. In a back pressure mechanism, a
back pressure chamber is formed at a rear surface of one scroll and
intermediate pressure oil or refrigerant is induced into the back
pressure chamber to render the scroll closely adhered to an
opposite scroll due to pressure applied by the back pressure
chamber. Typically, a tip seal mechanism is used with a low
pressure type scroll compressor, and a back pressure mechanism is
used with a high pressure type scroll compressor.
[0018] Scroll compressors may also be divided into a fixed capacity
type and a variable capacity type based on how refrigerant
circulates therethrough. That is, in a fixed capacity type scroll
compressor substantially all of the refrigerant discharged
therefrom circulates through a closed loop refrigerating cycle,
i.e., sequentially through the compressor, a condenser, an
expansion apparatus and an evaporator and then back into the
compressor. In a variable capacity type compressor, a portion of
the refrigerant discharged therefrom is bypassed at a middle
portion of a refrigerating cycle and introduced into an
intermediate compression chamber of the compressor, while the
remainder of the refrigerant sequentially flows through the devices
of a closed loop refrigerating cycle and is introduced back into
the compressor.
[0019] In a variable capacity type scroll compressor having a back
pressure passage through which an intermediate compression chamber
communicates with a back pressure chamber and an injection passage
through which an outlet of the condenser communicates with the
intermediate compression chamber of the compressor, an interval
between the back pressure passage and the injection passage may
adversely affect the performance of the compressor. That is, since
a refrigerant at intermediate pressure within the refrigerating
cycle is introduced into the intermediate compression chamber via
the injection passage, if the back pressure passage and the
injection passage are too close to a proceeding direction of a
compression chamber, the intermediate pressure refrigerant in the
injection passage may leak into the back pressure chamber via the
back pressure passage, thereby increasing the pressure inside the
back pressure chamber to an unacceptable level, thus not properly
maintaining pressure of the back pressure chamber. As a result, a
scroll supported by the pressure of the back pressure chamber may
be excessively adhered to or pressed against the opposite scroll,
thereby incurring frictional loss and abrasion of the wraps, and
degrading reliability and performance of the compressor.
[0020] As shown in FIG. 1, a high pressure type scroll compressor
as embodied and broadly described herein may include a casing 10
that forms a hermetic inner space, a main frame 20 and a sub frame
(not shown in FIG. 1) respectively positioned in an upper inner
space and a lower inner space of the casing 10, a driving motor 30
mounted between the main frame 20 and the sub frame for generating
a rotational force, a fixed scroll 40 fixed to an upper surface of
the main frame 20 and directly coupled to a gas suction pipe SP, an
orbiting scroll 50 positioned on the upper surface of the main
frame 20 so as to form compression chambers P through its
engagement with the fixed scroll 40, and an Oldham's ring installed
between the orbiting scroll 50 and the main frame 20 so that the
orbiting scroll 50 orbits without being rotated.
[0021] The hermetic inner space of the casing 10 may be divided
into an upper space S1 and a lower space S2 by the main frame 20
and the fixed scroll 40 so that both the upper and lower spaces S1
and S2 are maintained at a high pressure. A bottom portion of the
lower space S2 of the casing 10 may be filled with oil for
lubrication of the friction components of the compressor. The gas
suction pipe SP may penetrate the outer wall of the casing 10 so as
to communicate with the upper space S1 of the casing 10, while a
gas discharge pipe DP communicates with the lower space S2 of the
casing 10.
[0022] A shaft accommodation hole 21 may be formed through a center
of the main frame 20, and an oil pocket 22 in which oil drawn up
through an oil passage 32a of a driving shaft 32 may be formed at
an upper end of the shaft accommodation hole 21. A back pressure
groove 23 may be formed at an edge of the upper surface of the main
frame 20 so as to create a back pressure chamber S3 having an
intermediate pressure that is generated when a portion of
refrigerant and oil drawn in are mixed together. A sealing groove
may be formed in an annular shape within the back pressure groove
23 to receive a sealing member 60 therein such that oil collected
in the oil pocket 22 may be maintained at a high pressure. The back
pressure chamber S3 may be defined by a combination of the back
pressure groove 23 of the main frame 20, a plate portion 41 of the
fixed scroll 40 and a plate portion 51 of the orbiting scroll
50.
[0023] The driving motor 30 may include a stator secured to the
inside of the casing 10 and having a coil 31 to which external
power is supplied, a rotor disposed within the stator 31 with a
predetermined air gap therebetween so as to rotate by interaction
with the stator, and a driving shaft 32 coupled to the rotor by,
for example, a shrink fitting, for transferring the rotational
force of the driving motor 30 to the orbiting scroll 50. An oil
passage 32a may be formed through the driving shaft 32 in a
longitudinal direction of the shaft 32, and an oil pump may be
installed at a lower end of the oil passage 32a to pump oil from
the bottom of the casing 10 into the oil passage 32a.
[0024] The fixed scroll 40 may include fixed wraps 42 spirally
formed at a lower surface of the plate portion 41 so as to form a
pair of compression chambers P. An intake port 43 in direct
communication with the gas suction pipe SP may be formed at a side
surface of the plate portion 41, and a discharge port 44 through
which a compressed refrigerant is discharged up to the upper space
S1 of the casing 10 may be formed at a center of the upper surface
of the plate portion 41. A back pressure passage 110 that defines a
first passage between the compression chambers P and the back
pressure chamber S3 may be formed between the wraps 42 forming the
compression chambers P at a lower surface of the plate portion 41,
namely, at a surface thereof that defines a thrust bearing surface
together with the orbiting scroll 50.
[0025] The back pressure passage 110, as shown in FIGS. 2 to 4, may
include a first back pressure hole 111 that communicates with the
back pressure chamber S3, a second back pressure hole 112 that
communicates with the compression chamber P, and a third back
pressure hole 113 that provides for communication between the first
back pressure hole 111 and the second back pressure hole 112. A
communication groove 114 may be formed at an end of the first back
pressure hole 111, namely, at a surface facing the back pressure
groove 23, to provide for communication between the first back
pressure hole 111 and the back pressure groove 23. The
communication groove 114 may be radially formed and have a long,
substantially rectangular shape such that its width is greater than
that of the first back pressure hole 111. Diameters d1, d2 and d3
of the back pressure holes 111, 112 and 113, respectively may be
approximately the same so as to minimize flow resistance.
[0026] The first, second and third back pressure holes 111, 112 and
113 may define one passage that alternately communicates with the
pair of compression chambers P. That is, the second back pressure
hole 112 may be located between adjacent fixed wraps 42, and the
diameter d2 of the second back pressure hole 112 may be less than a
thickness t of the wrap 52 of the orbiting scroll 50, as shown in
FIG. 4 so as to prevent refrigerant leakage from an inner
compression chamber P to an outer compression chamber P due to a
pressure difference.
[0027] A blocking member 115 may be coupled to the third back
pressure hole 113. For example, in the embodiment shown in FIG. 4,
the blocking member 115 may be inserted into an external end of the
third back pressure hole 113 by a predetermined depth so as to
isolate the third back pressure hole 113 from the inner space of
the casing 10. In certain embodiments, the blocking member 115 may
be formed of a comparatively elastic non-ferrous metal so as to be
hermetically press-fitted within the external end of the third
bypass hole 113. Alternatively, as shown in FIGS. 3 and 4, the
blocking member 115 may be a metallic bolt that is threadly coupled
to a predetermined depth into the external end of the third bypass
hole 113. When using such a metallic bolt, a sealing washer 116 may
be hermetically inserted at a head portion of the metallic bolt for
coupling.
[0028] As shown in FIG. 1, the orbiting scroll 50 may include
orbiting wraps 52 spirally formed on an upper surface of a plate
portion 51 so as to form a pair of compression chambers P together
with the fixed wraps 42 of the fixed scroll 40. A boss portion 53
may extend from a central portion of a lower surface of the plate
portion 51 and be coupled to the driving shaft 32 so as to receive
a driving force from the driving motor 30.
[0029] In certain embodiments, the fixed wrap 42 and the orbiting
wrap 52 may be symmetrically formed with substantially the same
wrap length. In certain embodiments, they may be asymmetrically
formed with different wrap lengths. For example, the orbiting wrap
52 may be approximately 180.degree. longer than the fixed wrap 42.
Other arrangements may also be appropriate.
[0030] During operation, when power is applied to the driving motor
30, the driving shaft 32 rotates together with the rotor to
transfer a rotational force to the orbiting scroll 50. The orbiting
scroll 50 performs an orbiting motion by an eccentric distance on
the upper surface of the main frame 20 due to the Oldham's ring,
thereby forming a pair of compression chambers P which are
consecutively moved between the fixed wrap 42 of the fixed scroll
40 and the orbiting wrap 52 of the orbiting wrap 50. The volumes of
the compression chambers P are decreased as are moved toward the
center in response to the consecutive orbiting motion of the
orbiting scroll 50, thereby compressing refrigerant therein.
[0031] Simultaneously, an oil pump provided at the lower end of the
driving shaft 32 pumps oil contained in the casing 10 up via the
oil passage 32a of the driving shaft 32. A portion of the oil is
supplied into the shaft accommodation hole 21 of the main frame 20,
and a portion of the oil is dispersed at the upper end of the
driving shaft 32 so as to be introduced into the back pressure
chamber S3 of the main frame 20. The oil introduced into the back
pressure chamber S3 supports the orbiting scroll 50, which is
accordingly raised upward the fixed scroll 40. Hence, the fixed
wraps 42 and the orbiting wraps 52 are closely adhered to the
corresponding plate portions 51 and 41, respectively, thereby
sealing the compression chambers P.
[0032] In this state, refrigerant is compressed by the continuous
orbiting motion of the orbiting scroll 50. The compressed
refrigerant partially flows into the back pressure chamber S3 via
the back pressure passage 110, so that the pressure within the back
pressure chamber S3 may be maintained at a predetermined level.
Although only one outlet of the back pressure passage 110, namely,
the second back pressure hole 112, is provided, the second back
pressure hole 112 alternately communicates with both compression
chambers P as the orbiting scroll 50 orbits, allowing oil to be
uniformly supplied into each compression chamber P via the back
pressure passage 110.
[0033] In a variable capacity type compressor, refrigerant may be
reintroduced into an intermediate compression chamber of the
compressor at a middle portion of a refrigerating cycle, namely,
from an outlet of a condenser, so as to increase an amount of
refrigerant to be compressed, resulting in an increase in the
compression capacity of the compressor.
[0034] For example, as shown in FIG. 8, an injection pipe 6 may
diverge at a middle portion of a refrigerant pipe 5 that connects a
condenser 2 and an expansion apparatus 3 of the refrigerating
cycle, namely, at an outlet of the condenser 2. The injection pipe
6 may be connected to an injection passage 120 that forms a second
passage at the fixed scroll 40 of the scroll compressor 1 shown in
FIGS. 1 and 2. A bypass valve 7 for controlling the flow of
refrigerant through the injection pipe 6 may be installed at a
middle portion of the injection pipe 6 or at an area where the
injection pipe 6 diverges from the refrigerant pipe 5.
[0035] The injection passage 120, as shown in FIGS. 2, 3 and 5, may
include a first injection hole 121 formed in a radial direction at
a predetermined depth in the fixed scroll 40, and a second
injection hole 122 that extends in a shaft direction from an end
portion of the first injection hole 121 through the intermediate
compression chamber.
[0036] Depending on the position of the second injection hole 122,
refrigerant injected therethrough from the middle portion of the
refrigerating cycle may leak into the back pressure chamber S3,
possibly degrading compression performance. In order to enhance
performance of the compressor, specific positioning of the
injection passage 120 with respect to the back pressure passage
110, and more particularly, the second back pressure hole 112 of
the back pressure passage 110 and the second injection passage 122
of the injection passage 120, may be established.
[0037] To this end, the second injection hole 122 of the injection
passage 120 may be formed, as shown in FIGS. 6 and 7, closer to the
discharge side of the compression chamber than the second back
pressure hole 112 of the back pressure passage 110. More
particularly, the second injection hole 122 may be formed so that
an angle at which a refrigerant starts to be injected into the
intermediate compression chamber P and an angle at which the
refrigerant within the intermediate compressor chamber starts to be
introduced into the back pressure chamber S3 is greater than
approximately 30.degree.. Consequently, leakage of the refrigerant
injected into the intermediate compression chamber via the
injection passage 120 into the back pressure passage 110 may be
prevented. The greater the phase difference between the second back
pressure passage 112 of the back pressure passage 110 and the
second injection passage 122 of the injection passage 120, the
greater the leakage prevention.
[0038] A diameter 24 of the second injection hole 122 may be
substantially the same as a diameter of the second back pressure
hole 112, so as to smoothly control the amount of refrigerant
injected. The diameter d4 of the second injection hole 122 may be
less than a thickness t of the orbiting wrap 52 of the orbiting
scroll 50 so as to prevent a refrigerant injected via the injection
passage 120 from being leaked into both the compression chambers P
due to the injection passage 120 communicating with the compression
chambers P.
[0039] A temperature of the refrigerant injected into the
intermediate compression chamber may be lower than a temperature at
the outlet of the condenser 2 but higher than a temperature at a
suction side of the compression chamber P, so as to increase the
amount of the refrigerant to be injected. That is, as shown in FIG.
8, after a refrigerant discharged from the compressor 1 flows
through the condenser 2, part of the refrigerant is bypassed into
the injection pipe 6 at the outlet of the condenser 2. The high
temperature and high pressure bypassed liquid refrigerant is
expanded and converted into a mixed refrigerant (gaseous
refrigerant+liquid refrigerant) with a temperature of about
20.degree. C. The mixed refrigerant is re-heat-exchanged via a
re-heat exchanger 6a positioned between the condenser 2 and the
injection pipe 6 for heat exchange with the condenser 2 so as to be
converted into a low temperature gaseous refrigerant. The low
temperature gaseous refrigerant is then injected into the
intermediate compression chamber via the injection passage 120.
[0040] As described above, in a scroll compressor 1 having the back
pressure passage 110 and the injection passage 120, if an angle a
formed between the back pressure passage 110 and the injection
passage 120 is greater than approximately 30.degree., the actual
pressure within the back pressure chamber 53, as shown in FIG. 9A,
may be maintained substantially close to/at the design pressure,
thereby stably supporting the orbiting scroll 50. If the angle a
therebetween is 20.degree., the actual pressure within the back
pressure chamber, as shown in FIG. 9B, is greater than the design
pressure, which may cause the orbiting scroll 50 to be excessively
raised and pressed against the fixed scroll 40. Accordingly,
frictional loss or abrasion may occur between the orbiting scroll
50 and the fixed scroll 40, thereby lowering the performance and/or
reliability of the compressor 1.
[0041] Consequently, the angle between the injection passage 120
and the back pressure passage 110 may maintain an appropriate phase
difference, or angle a therebetween, so as to effectively prevent a
refrigerant injected into the intermediate compression chamber via
the injection passage from leaking into the back pressure chamber
via the back pressure passage without flowing along the proceeding
direction of the compression chamber. Hence, during a high capacity
operation of the scroll compressor, a refrigerant injected into the
intermediate compression chamber via the injection passage at the
middle portion of the refrigerant cycle may be combined with a
refrigerant sucked into a suction side of the compression chamber,
thereby increasing the amount of refrigerant to be compressed,
resulting in improved performance.
[0042] Similarly, if a scroll compressor as embodied and broadly
described herein is applied to a refrigerating apparatus, the
efficiency of the refrigerating apparatus may also be improved.
[0043] As shown in FIG. 10, an exemplary refrigerating apparatus
700 as embodied and broadly described herein may include a
refrigerant compression type refrigerating cycle provided with a
scroll compressor 1, a condenser 2, an expansion apparatus 3, and
an evaporator 4 as shown in FIG. 8. The compressor 1 may include an
injection passage through which a portion of refrigerant flowing
through the condenser 2 is injected back into an intermediate
compression chamber of the scroll compressor 1. Within the
refrigerating apparatus 700, the scroll compressor 1 may be
connected to a main substrate 710, which controls an overall
operation of the refrigerating apparatus 700. A fixed scroll
installed within the scroll compressor 1 may include a back
pressure passage through which refrigerant is discharged from the
intermediate compression chamber into a back pressure chamber, and
an injection passage through which refrigerant flows back into the
intermediate compression chamber via an outlet of the condenser 2.
The back pressure passage and the injection passage may form an
angle therebetween of at least more than 30.degree., as described
above. Consequently, leakage of the refrigerant injected into the
intermediate compression chamber via the injection passage into the
back pressure passage may be prevented, resulting in improved
performance of the refrigerating apparatus having such a scroll
compressor.
[0044] In the scroll compressor according to the present invention
and a refrigerating apparatus having the same, leakage of the
refrigerant from the intermediate compression chamber into the back
pressure chamber may be prevented, thereby appropriately
maintaining the pressure of the back pressure chamber, and also
increasing the amount of refrigerant within the compression
chamber, resulting in improved performance of the scroll compressor
and the refrigerating apparatus in which it is installed.
[0045] A scroll compressor as embodied and broadly described herein
may be applied to numerous different types of refrigerating
apparatuses, such as, for example, an air conditioning apparatus, a
refrigerating/freezing apparatus, or other refrigerating apparatus
in which compression of refrigerant is employed.
[0046] A scroll compressor as embodied and broadly described herein
is capable of maintaining an appropriate pressure inside the back
pressure chamber by preventing a refrigerant, injected from the
refrigerating cycle into the intermediate pressure via the
injection passage, from being drastically leaked from the
intermediate compression chamber into the back pressure chamber,
and a refrigerating apparatus having the same.
[0047] A scroll compressor as embodied and broadly described herein
may include compression chambers formed to be consecutively moved
as a plurality of scrolls perform a relative motion with being
engaged with each other, a back pressure chamber formed at a
bearing surface at which the plurality of scrolls come in contact
with each other and configured to support the neighboring scrolls,
a first passage formed at a scroll and configured so that part of
refrigerant compressed in the compression chambers is bypassed to
be guided into the back pressure chamber, and a second passage
formed at a scroll and configured so that part of refrigerant
discharged from the compression chambers into a refrigerating cycle
is bypassed at a middle portion of the refrigerating cycle to be
supplied back into the compression chambers.
[0048] A scroll compressor in accordance with another embodiment as
broadly described herein may include a fixed scroll having spiral
wraps, and an orbiting scroll having spiral wraps, the spiral wraps
orbiting with being engaged with the wraps of the fixed scroll so
as to form a pair of compression chambers consecutively moved
during the orbiting motion, a back pressure chamber for containing
a refrigerant bypassed from the compression chambers being formed
at a rear surface of the orbiting scroll, wherein the fixed scroll
is provided with at least one back pressure passage formed at the
fixed scroll for communicating the compression chambers with the
back pressure chamber, and an injection passage through which part
of a refrigerant discharged from the compression chambers into the
refrigerating cycle is injected back into the compression
chambers.
[0049] A refrigerating apparatus as embodied and broadly described
herein may include a compressor, a condenser connected to a
discharge side of the compression, an expansion apparatus connected
to the condenser, and an evaporator connected to the expansion
apparatus and to a suction side of the compressor, wherein the
compressor is a scroll compressor configured so that an angle
between an injection passage communicating with an intermediate
compression chamber at a middle portion of a refrigerating cycle
and a back pressure passage is approximately more than
30.degree..
[0050] Any reference in this specification to "one embodiment," "an
embodiment," "example embodiment," etc., means that a particular
feature, structure, or characteristic described in connection with
the embodiment is included in at least one embodiment of the
invention. The appearances of such phrases in various places in the
specification are not necessarily all referring to the same
embodiment. Further, when a particular feature, structure, or
characteristic is described in connection with any embodiment, it
is submitted that it is within the purview of one skilled in the
art to effect such feature, structure, or characteristic in
connection with other ones of the embodiments.
[0051] Although embodiments have been described with reference to a
number of illustrative embodiments thereof, it should be understood
that numerous other modifications and embodiments can be devised by
those skilled in the art that will fall within the spirit and scope
of the principles of this disclosure. More particularly, numerous
variations and modifications are possible in the component parts
and/or arrangements of the subject combination arrangement within
the scope of the disclosure, the drawings and the appended claims.
In addition to variations and modifications in the component parts
and/or arrangements, alternative uses will also be apparent to
those skilled in the art.
* * * * *