U.S. patent application number 12/181987 was filed with the patent office on 2009-02-05 for compressor.
Invention is credited to Nam-Kyu Cho, Yang-Hee Cho, Cheol-Hwan Kim, Hyo-Keun Park, Dong-Koo Shin, Byung-Kil YOO.
Application Number | 20090031753 12/181987 |
Document ID | / |
Family ID | 40029310 |
Filed Date | 2009-02-05 |
United States Patent
Application |
20090031753 |
Kind Code |
A1 |
YOO; Byung-Kil ; et
al. |
February 5, 2009 |
COMPRESSOR
Abstract
A compressor is provided that includes a casing defining an
inner space, a suction pipe connected to the casing, a discharge
pipe connected to the casing, a motor located at the inner space of
the casing, a compressing unit driven by the motor to compress a
refrigerant, an oil separating unit configured to separate oil from
the refrigerant discharged from the compressing unit, and an oil
recollecting unit configured to pump the oil separated by the oil
separating unit and recollect the separated oil into the compressor
main body.
Inventors: |
YOO; Byung-Kil; (Seoul,
KR) ; Cho; Nam-Kyu; (Seoul, KR) ; Shin;
Dong-Koo; (Seoul, KR) ; Cho; Yang-Hee; (Seoul,
KR) ; Park; Hyo-Keun; (Seoul, KR) ; Kim;
Cheol-Hwan; (Seoul, KR) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
40029310 |
Appl. No.: |
12/181987 |
Filed: |
July 29, 2008 |
Current U.S.
Class: |
62/470 ;
62/469 |
Current CPC
Class: |
F04C 2240/806 20130101;
F04C 2/102 20130101; F25B 31/004 20130101; F01C 11/004 20130101;
F04C 23/008 20130101; F04C 29/026 20130101; F04C 2210/14 20130101;
F25B 2400/02 20130101; F04C 29/045 20130101; F04C 29/025 20130101;
F25B 43/02 20130101; F04C 15/06 20130101 |
Class at
Publication: |
62/470 ;
62/469 |
International
Class: |
F25B 43/02 20060101
F25B043/02; F25B 43/00 20060101 F25B043/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 30, 2007 |
KR |
10-2007-0076579 |
Dec 27, 2007 |
KR |
10-2007-0139286 |
Jul 18, 2008 |
KR |
10-2008-0070336 |
Claims
1. A compressor comprising: a compressor main body including a
casing defining an inner space; a suction pipe connected to the
casing; a discharge pipe connected to the casing; a motor installed
at the inner space of the casing; a compressing unit driven by the
motor to compress a refrigerant; an oil separating unit configured
to separate oil from the refrigerant discharged from the
compressing unit; and an oil recollecting unit configured to pump
the oil separated by the oil separating unit and recollect the
separated oil into the compressor main body.
2. The compressor of claim 1, wherein the oil recollecting unit
includes an oil recollecting pipe connected to the oil separating
unit.
3. The compressor of claim 2, wherein the oil separating unit is
located outside of the casing of the compressor main body, the oil
separating unit having an inlet connected to the compressor main
body via the discharge pipe and an outlet connected to the
compressor main body via the oil recollecting pipe.
4. The compressor of claim 3, wherein the oil recollecting pipe has
one end connected to the compressor main body and another end
connected to the outlet of the oil separating unit.
5. The compressor of claim 3, wherein the oil separating unit is
supported by a supporting member fixed to an outer circumferential
surface of the casing of the compressor main body.
6. The compressor of claim 2, wherein the oil recollecting unit
includes an oil recollecting pump disposed at an intermediate
portion of the oil recollecting pipe to pump oil separated by the
oil separating unit.
7. The compressor of claim 1, wherein the oil separating unit is
located inside the casing of the compressor main body.
8. The compressor of claim 7, wherein the oil recollecting unit
includes an oil recollecting pipe located inside the casing of the
compressor main body to guide oil separated by the oil separating
unit.
9. The compressor of claim 7, wherein the oil recollecting unit
includes an oil recollecting pipe to guide oil separated by the oil
separating unit, and wherein at least a portion of the oil
recollecting pipe is located outside the casing of the compressor
main body.
10. The compressor of claim 7, wherein the oil separating unit
includes: an inner space; and an oil separating pipe to guide the
separated oil, the oil separating pipe being bent or curved such
that a refrigerant introduced into the inner space of the oil
separating unit spirally orbits.
11. The compressor of claim 1, wherein the compressing unit
includes: a fixed scroll fixedly installed at the casing; and an
orbiting scroll engaged with the fixed scroll and orbiting in
cooperation with the motor, the fixed scroll and orbiting scroll
defining at least one compression chamber.
12. The compressor of claim 1, wherein the inner space of the
casing is a hermetic inner space.
13. A compressor comprising: a casing having an inner space; a
suction pipe connected to the casing; a discharge pipe connected to
the casing; a motor located in the inner space of the casing to
generate a driving force; a compressing unit driven by the motor to
compress a refrigerant; an oil separating unit configured to
separate oil from the refrigerant discharged out of the compressing
unit; and an oil recollecting unit including an oil recollecting
pump driven by a rotation force of the motor to pump oil separated
by the oil separating unit.
14. The compressor of claim 13, wherein the motor includes: a
crankshaft; and wherein the oil recollecting pump includes: an
inner gear coupled to the crankshaft of the motor; an outer gear
engaged with the inner gear to generate a variable capacity; and an
inlet to receive oil separated by the oil separating unit.
15. The compressor of claim 13, wherein the oil recollecting pump
includes a first inlet connected to the oil separating unit and a
second inlet in communication with the inner space of the
casing.
16. The compressor of claim 15, wherein the crankshaft of the motor
includes an oil passage located therein, the oil passage extending
in an axial direction of the crankshaft, and wherein the oil
recollecting pump includes an outlet in communication with the
first and second inlets, the outlet being in communication with the
oil passage located in the crankshaft.
17. The compressor of claim 13, further comprising an oil supplying
pump disposed at one side of the oil recollecting pump, wherein the
motor includes a crankshaft, and the oil supplying pump is coupled
to the crankshaft of the motor to rotate together with the oil
recollecting pump, thereby pumping oil contained in the casing.
18. The compressor of claim 17, wherein the oil supplying pump
includes an inlet and an outlet, the oil recollecting pump includes
an inlet and an outlet, and the inlet and outlet of the oil
supplying pump are arranged independent of the inlet and outlet of
the oil recollecting pump.
19. A compressor comprising: a casing having an inner space; a
suction pipe connected to the casing; a discharge pipe connected to
the casing; a motor located in the inner space of the casing to
generate a driving force; a compressing unit driven by the motor to
compress a refrigerant; an oil separating unit configured to
separate oil from the refrigerant discharged out of the compressing
unit; and an oil recollecting unit including: an oil recollecting
pipe for connecting the oil separating unit to the casing; and an
oil recollecting pump cooperating with the oil recollecting pipe to
pump oil separated by the oil separating unit.
20. The compressor of claim 19, wherein the oil recollecting pipe
has an outlet in communication with the inner space of the
casing.
21. The compressor of claim 20, wherein the motor includes a
crankshaft and the oil recollecting pipe includes an outlet, the
compressor further comprising: an oil supplying pump having an
inlet, the oil supplying pump being located at the crankshaft to
pump oil contained in the casing while rotating together with the
crankshaft, and the outlet of the oil recollecting pipe being
connected to the inlet of the oil supplying pump.
22. The compressor of claim 19, wherein the oil recollecting pump
includes an inverter motor such that a pumping amount is variable
in proportion to a rotation velocity of the motor.
23. The compressor of claim 19, wherein the oil recollecting pump
is located at an intermediate portion of the oil recollecting pipe.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to Korean
Applications No. 10-2007-0076579, filed on Jul. 30, 2007, Korean
Application No. 10-2007-0139286, filed on Dec. 27, 2007, and Korean
Application No. 10-2008-0070336, filed on Jul. 18, 2008, which are
herein expressly incorporated by reference in their entireties.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to a compressor,
and, more particularly, to an oil recollecting apparatus of a
compressor capable of separating and recollecting oil from a
refrigerant discharged from a compressing unit.
[0004] 2. Description of Related Art
[0005] A compressor is a device for converting kinetic energy into
compression energy of a compressive fluid. A hermetic compressor is
configured such that a motor for generating a driving force and a
compression unit for compressing fluid by the driving force
received from the motor are all installed in an inner space of a
hermetically sealed container.
[0006] When the hermetic compressor is provided as a component in a
refrigerant compression refrigeration cycle, a certain amount of
oil is stored in the hermetic compressor in order to cool the motor
of the compressor or smooth and seal the compression unit. However,
when the compressor is driven, the refrigerant discharged from the
compressor into the refrigeration cycle includes oil mixed in with
the refrigerant. Part of the oil discharged into the refrigeration
cycle is not recollected to the compressor but remains in the
refrigeration cycle, thereby causing a decrease in the amount of
oil in the compressor. This may result in decrease in compressor
reliability and also degradation of heat-exchange capability of the
refrigeration cycle due to the oil remaining in the refrigeration
cycle.
[0007] Accordingly, in the related art, an oil separator is
disposed at a discharge side of the compressor to separate oil from
the discharged refrigerant, and such separated oil is recollected
to a suction side of the compressor, thereby avoiding the lack of
oil in the compressor and also maintaining the heat-exchange
capability of the refrigeration cycle.
[0008] However, when recollecting oil separated by the oil
separator into the suction side of the compressor, the high
pressure refrigerator is also recollected together with the oil,
which results in decreasing the amount of refrigerant circulating
in the refrigeration cycle, thereby lowering a cooling capability
of the compressor. In addition, temperature of suction gas in the
compressor is increased to thereby raise temperature of discharge
gas. Accordingly, the reliability of the compressor is degraded.
Also, as the temperature increases, a specific volume of the sucked
refrigerant is increased, so as Lo decrease he actual amount of the
sucked refrigerant, thereby degrading the cooling capability.
[0009] Specifically, during a low speed operation of the
compressor, the lack of oil pumped causes cooling refrigerant gas
to be more recollected than oil, whereby the amount of refrigerant
circulating in the refrigeration cycle is decreased. Accordingly,
the cooling capability of the compressor is further degraded.
BRIEF SUMMARY OF THE INVENTION
[0010] Therefore, in order to solve those problems of the related
art compressor, an object of the present invention is to provide a
compressor having an oil recollecting apparatus for recollecting
oil separated from a refrigerant discharged from a compressing
unit.
[0011] To achieve these and other advantages and in accordance with
the purpose of the present invention, as embodied and broadly
described herein, there is provided a compressor having a
compressor main body including a casing defining an inner space, a
suction pipe corrected to the casing, a discharge pipe connected to
the casing, a motor located at the inner space of the casing, a
compressing unit driven by the motor to compress a refrigerant, an
oil separating unit configured to separate oil from the refrigerant
discharged from the compressing unit, and an oil recollecting unit
configured to pump the oil separated by the oil separating unit and
recollect the separated oil into the compressor main body.
[0012] According to a different aspect of the present invention,
there is provided a compressor having a casing having an inner
space, a suction pipe connected to the casing, a discharge pipe
connected to the casing, a motor located in the inner space of the
casing to generate a driving force, a compressing unit driven by
the motor to compress a refrigerant, an oil separating unit
configured to separate oil from the refrigerant discharged out of
the compressing unit, and an oil recollecting unit including an oil
recollecting pump driven by a rotation force of the motor to pump
oil separated by the oil separating unit.
[0013] According to yet another aspect of the present invention,
there is provided a compressor having a casing having an inner
space, a suction pipe connected to the casing, a discharge pipe
connected to the casing, a motor located in the inner space of the
casing to generate a driving force, a compressing unit driven by
the motor to compress a refrigerant, an oil separating unit
configured to separate oil from the refrigerant discharged out of
the compressing unit, and an oil recollecting unit. The oil
recollecting unit includes an oil recollecting pipe for connecting
the oil separating unit to the casing and an oil recollecting pump
cooperating with the oil recollecting pipe to pump oil separated by
the oil separating unit.
[0014] Further scope of applicability of the present application
will become more apparent from the detailed description given
hereinafter. However, it should be understood that the detailed
description and specific examples, while indicating exemplary
embodiments of the invention, are given by way of illustration
only, since various changes and modifications within the spirit and
scope of the invention will become apparent to those skilled in the
art from the detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The accompanying drawings, which are included to provide a
further understanding of the invention and are incorporated in and
constitute a part of this specification, illustrate embodiments of
the invention and together with the description serve to explain
the principles of the invention. In the drawings:
[0016] FIG. 1 is a perspective view showing an outer appearance of
a scroll compressor having an oil separating unit disposed outside
a casing according to the present invention;
[0017] FIG. 2 is a longitudinal sectional view showing an inside of
the scroll compressor of FIG. 1;
[0018] FIG. 3 is a perspective view showing an oil supplying pump
and an oil recollecting pump of FIG. 1;
[0019] FIG. 4 is a longitudinal sectional view showing another
exemplary embodiment of the oil recollecting unit according to the
present invention, and FIG. 4A is a detailed view of the inlets of
the oil recollecting unit as designated by call-out A of FIG.
4;
[0020] FIG. 5 is a schematic view showing an inlet of the oil
recollecting pump of FIG. 4;
[0021] FIG. 6 is a longitudinal sectional view showing another
exemplary embodiment of a scroll compressor having an oil
separating unit disposed outside a casing according to the present
invention;
[0022] FIG. 7 is a longitudinal sectional view showing an exemplary
embodiment of a scroll compressor having an oil separating unit
disposed inside a casing according to the present invention;
[0023] FIG. 8 is a horizontal sectional view showing a fluid
flowing state in an oil separating cap of FIG. 7; and
[0024] FIG. 9 is a longitudinal section view showing another
exemplary embodiment of a scroll compressor having an oil
separating unit disposed outside a casing according to the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0025] Description will now be given in detail of the present
invention, with reference to the accompanying drawings. Although
the description of the present invention is given with reference to
scroll compressors, the present invention is not limited to scroll
compressors, but can be equally applied to other so-called hermetic
compressors, such as rotary compressors, having a motor and a
compressing unit disposed in the same casing.
[0026] FIG. 1 is a perspective view showing an outer appearance of
a scroll compressor according to a first exemplary embodiment of
the present invention where an oil separating unit is disposed
outside a casing, FIG. 2 is a longitudinal sectional view showing
an inside of the scroll compressor of FIG. 1, and FIG. 3 is a
perspective view showing an oil supplying pump and an oil
recollecting pump of FIG. 1
[0027] As shown in FIGS. 1 to 3, the scroll compressor according to
the present invention may include a compressor casing (hereinafter,
referred to as `casing`) 10 having a hermetic inner space, a motor
20 located in the inner space of the casing 10, and a compressing
unit 30 driven by the motor 20. The compressing unit 30 includes a
fixed scroll 31 and an orbiting scroll 32 driven by the motor 20 to
compress a refrigerant.
[0028] The inner space of the casing 10 is configured to hold a
refrigerant at a suitable discharge pressure. A suction pipe SP is
formed through one side of the casing 10 to be in communication
with a suction chamber formed by the fixed scroll 31 and the
orbiting scroll 32. A discharge pipe DP is connected to another
side of the casing 10 to guide a refrigerant discharged out of the
inner space of the casing 10 to a refrigeration cycle.
[0029] The motor 20 may be a constant speed motor rotating at a
uniform speed, or an inverter motor rotating at variable speed
depending on the needs of a refrigerating device to which the
compressor is applied. A crankshaft 23 of the motor 20 is supported
by a main frame 11 and a sub-frame 12 fixedly installed at both
upper and lower ends of the casing 10.
[0030] An oil passage 23a is formed through the crankshaft 23 in an
axial direction. An oil supplying pump 25 for pumping oil contained
in the casing 10 is disposed below the oil passage 23a, in
particular, below the crankshaft 23. A displacement pump may be
used as the oil supplying pump 25 as shown in FIG. 2. An example of
such a displacement pump includes a trochoid gear pump which forms
a variable capacity between an inner gear and an outer gear so as
to pump oil. An oil suction pipe 26 is connected to an inlet of the
oil supplying pump 25 to suck oil located in a bottom of the casing
10. The oil suction pipe 26 has an inlet with a suitable length so
as to extend into the oil contained at the bottom of the casing
10.
[0031] The compressing unit 30, as shown in FIG. 2, includes the
fixed scroll 31 coupled to the main frame 11, the orbiting scroll
32 engaged with the fixed scroll 31 to provide a pair of
compression chambers P which continuously move, an Oldham ring 33
disposed between the orbiting scroll 32 and the main frame 11 to
induce the orbiting motion of the orbiting scroll 32, and a check
valve 34 disposed to switch a discharge opening 31c of the fixed
scroll 31 so as to block a backflow of discharge gas discharged
through the discharge opening 31c. A fixed wrap 31a and an orbiting
wrap 32a are spirally provided at the fixed scroll 31 and the
orbiting scroll 32, respectively. The fixed wrap 31a and the
orbiting wrap 32a are engaged with each other to form the
compression chambers P. The suction pipe SP is directly connected
to a suction opening 31b of the fixed scroll 31 for guiding a
refrigerant from the refrigeration cycle into the compressor.
[0032] Operation of the compressor will be described with reference
to the above configuration. When power is applied to the motor 20,
the crankshaft 23 rotates together with a rotor 22 to forward such
rotational force to the orbiting scroll 32. The orbiting scroll 32
receiving the rotational force applied is then orbited by the
Oldham ring 33 on an upper surface of the main frame 11, thereby
forming a pair of compression chambers P which are continuously
moved between the fixed wrap 31a of the fixed scroll 31 and the
orbiting wrap 32a of the orbiting scroll 32. Such compression
chambers P are then moved to the center by the continuous orbiting
motion of the orbiting scroll 32 such that their capacities
decrease to thereby compress a sucked refrigerant. The compressed
refrigerant is continuously discharged to an upper space S1 of the
casing 10 through the discharge opening 31c of the fixed scroll 31
and then moved down to a lower space S2 of the casing 10, thereby
being discharged into a refrigeration cycle system through the
refrigerant discharge pipe DP. The compressed refrigerant may be
moved from upper space S1 to lower space S2 using various
approaches, such as, for example providing a passage (not shown)
through the fixed scroll 31 and/or main frame 11.
[0033] At the same time that the crankshaft 23 is rotated, the oil
supplying pump 25 disposed below the crankshaft 23 pumps oil
contained in the casing 10 using a variable capacity formed between
the inner gear and outer gear of the oil supplying pump 25. Oil is
sucked toward an upper end through the oil passage 23a of the
crankshaft 23 and the oil is partially supplied to respective
bearing surfaces of the sub-frame 12 and the main frame 11, and
partially supplied to the compression chambers P through a bearing
surface between the main frame 11 and the orbiting scroll 12 at the
upper end of the crankshaft 23 so as to seal or smooth the
compression chambers P.
[0034] An oil recollecting pump 52 coupled to the crankshaft 23
configured to operate in cooperation with the oil supplying pump 25
is also provided. The oil recollecting pump 52 pumps and recollects
oil separated from a refrigerant discharged out of the compressing
unit. A detailed description thereof will now be given.
[0035] As shown in FIGS. 1 and 2, an oil separating unit 40 for
separating oil from a refrigerant discharged into the refrigeration
cycle through the discharge pipe DP is located at an outlet portion
of the discharge pipe DP outside the casing 10. In addition, an oil
recollecting unit 50 is connected to the oil separating unit 40.
The oil recollecting unit 50 is configured to pump oil separated
from a refrigerant by the oil separating unit 40 and to either
recollect the separated oil in the inner space of the casing 10
(See FIG. 6) or to recollect such oil directly into the oil passage
23a of the crankshaft 23.
[0036] As shown in FIGS. 1 and 2, the oil separating unit 40 may
include an oil separator 41 disposed in parallel with one side of
the casing 10, and an oil separating member (not shown) disposed at
the oil separator 41 to separate oil from a refrigerant discharged
from the compressing unit 30. The oil separator 41 may be supported
by being connected to the discharge pipe DP at its middle portion
or supported by a supporting member 42 (e.g., a clamp) separately
disposed between the casing 10 and the oil separator 41. A
refrigerant pipe RP is connected to an upper end of the oil
separator 41 to allow the separated refrigerant to flow toward a
condenser of the refrigeration cycle. An oil recollecting pipe 51
is connected to a lower end of the oil separator 41 such that oil
separated by the oil separator 41 can be recollected into the
casing 10 of the compressor or directly into the compressing unit
30 via the oil passage 23a.
[0037] The oil separating unit 40 may use various methods for
separating oil. For example, a mesh screen may be installed inside
the oil separator 41 to thereby separate oil from a refrigerant, or
the discharge pipe DP may be connected to the oil separator 41 at
an incline such that a refrigerant rotates in a form of cyclone to
thereby separate relatively heavy oil from the refrigerant.
[0038] The oil recollecting unit 50 may include the oil
recollecting pipe 51 connected to the oil separating unit 40 to
guide oil, and an oil recollecting pump 52 installed at the oil
recollecting pipe 51 to pump oil from the oil separator 41. One end
of the oil recollecting pipe 51 is connected to the lower end of
the oil separator 41, and the other end thereof penetrates through
the casing 10 to be connected to an inlet of the oil recollecting
pump 52. The oil recollecting pipe 51 may be a metallic pipe having
a suitable strength so as to stably support the oil separator 41.
Also, the oil recollecting pipe 51 may be curved through an angle
so that the oil separator 41 is oriented parallel with the casing
10, thus to reduce a vibration of the compressor.
[0039] The oil recollecting pump 52 may be installed above or below
the oil supplying pump 25 to be driven by a driving force from the
motor 20. For example, as shown in FIG. 3, the oil recollecting
pump 52 may be a trochoid gear pump in which an inner gear is
coupled to the crankshaft 23 of the motor 20 and the inner gear is
engaged with an outer gear to provide a variable capacity. An
outlet of the oil recollecting pump 52 is in communication with an
outlet of the oil supplying pump 25 such that oil recollected
through the oil recollecting pump 52 can be introduced into the oil
passage 23a of the crankshaft 23 together with oil sucked through
the oil supplying pump 25. In some cases, the outlet of the oil
recollecting pump 52 and the outlet of the oil supplying pump 25
may be independently formed to allow oils from each of them to be
independently introduced into the oil passage 23a of the crankshaft
23.
[0040] In the scroll compressor according to this exemplary
embodiment, the oil separator 41 separates oil from a refrigerant
discharged out of the inner space of the casing 10. Such separated
oil is recollected into the inner space of the casing 10 via the
oil recollecting pump 52, or may be directly be supplied into the
oil passage 23a of the crankshaft 23. For example, oil introduced
into the compression chamber P is discharged together with a
refrigerant to be introduced into the oil separator 41 via the
discharge pipe DP. Such oil and refrigerant are separated from each
other in the oil separator 41. The separated refrigerant then flows
up to a condenser of the refrigeration cycle via the refrigerant
pipe RP whereas the separated oil is collected at the bottom of the
oil separator 41. As the crankshaft 23 of the motor 20 rotates, the
inner gear of the oil recollecting pump 52 rotates so as to
configure a variable capacity between the inner gear and the outer
gear, thereby generating a pumping force. The oil separated by the
oil separator 41 is pumped by such pumping force. The oil pumped by
the oil recollecting pump 52 is recollected into the inner space of
the casing 10 through the oil recollecting pipe 51 and the oil
recollecting pump 52. Such recollected oil is accordingly
re-supplied to each bearing surface and the compression chamber P
by the oil supplying pump 52 via the oil passage 23a of the
crankshaft 23. This process may be continuously repeated as the
crankshaft 23 rotates.
[0041] An oil supplying hole 14 for injecting oil into the inner
space of the casing 10 may be formed at a lower portion of the
casing 10. When a plurality of compressors are used, the oil
supplying hole 14 may be used as an oil equalizing hole to place
the plurality of compressors in communication with each other in
order to match liquid-level heights of each of the compressors.
[0042] While the first exemplary embodiment of the compressor
includes an oil supplying pump, a second exemplary embodiment is
provided where a single oil recollecting pump is used to perform
the function of the oil supplying pump. For example, the second
exemplary embodiment of the scroll compressor may be implemented as
follows. As shown in FIGS. 4 and 5, the oil recollecting pump 52,
which may be a trochoid gear pump, is installed below the
crankshaft 23, and a first inlet 52a of the oil recollecting pump
52 is connected to an outlet of the oil recollecting pipe 51 while
a second inlet 52b of the oil recollecting pump 52 is sunk in oil
collected at the bottom of the casing 10.
[0043] The scroll compressor in accordance with this exemplary
embodiment is similar to that of the aforesaid embodiment in the
basic configuration and operations, and accordingly a detailed
description thereof will not be repeated. However, the inlet of the
oil recollecting pump 52 is divided into the first inlet 52a and
the second inlet 52b. Accordingly, oil separated by the oil
separator 41 is sucked through the first inlet 52a while oil
collected at the bottom of the casing 10 is sucked through the
second inlet 52b. Such oils sucked through the first and second
inlets 52a and 52b are all collected into the oil passage 23a of
the crankshaft 23 to be supplied to each bearing surface or the
compression chamber P.
[0044] Still another embodiment of a scroll compressor according to
the present invention will be described hereafter. While the
aforementioned exemplary embodiments are configured such that the
oil recollecting pump is installed inside the casing or coupled to
the motor to use the driving force of the motor, a third exemplary
embodiment of the scroll compressor, as shown in FIG. 6, is
configured such that an oil recollecting pump 152 of an oil
recollecting unit 150 is installed outside the casing 10, and is
driven by a separate driving force, other than the driving force of
the motor. To this end, the oil recollecting pump 152 is installed
at an intermediate portion of the oil recollecting pipe 151 at the
outside of the casing 10, and an inverter motor having a rotation
velocity, which can be changed (increase or decrease), in
proportion to the rotation velocity of the motor 20 is provided.
The oil recollecting pipe 151 may have an outlet which is directly
connectable to the oil passage 23a of the crankshaft 23, however,
in some cases, it may be connected to the inner space of the casing
10. As shown in this exemplary embodiment, when the oil
recollecting pipe 151 is in communication with the inner space of
the casing 10 instead of directly with the oil passage 23a, foreign
materials contained in the oil may be filtered upward in the inner
space of the casing 10 so as to prevent contamination of the oil
supplied to each bearing surface or the compression chambers P.
[0045] According to yet another exemplary embodiment of the present
invention, the oil separating unit may be located at the inside of
the casing of the compressor. For example, as shown in FIG. 7, an
oil separating unit 240 may include an oil separating cap 241
fixedly installed in the inner space of the casing 10 and an oil
separating pipe 242 formed through one side wall surface of the oil
separating cap 241 such that oil and refrigerant inside the casing
10 can be separated from each other while being introduced into the
oil separating cap 241. The oil separating cap 241 may have a gap
spaced apart from the inner surface of the casing 10.
[0046] A guide cover 15 having a certain inner space to accommodate
a discharge side of the compressing unit 30 is installed between
the compressing unit 30 and the oil separating unit 240. An inlet
side fluid passage (not shown) is formed at a portion of the
compressing unit 30 which is accommodated in the guide cover 15,
whereas an outlet side fluid passage (not shown) is formed at a
portion of the compressing unit 30 which is not accommodated in the
guide cover 15. Accordingly, refrigerant and oil discharged from
the compression chamber P is allowed to flow toward a lower space
S2 of the casing 10, namely, toward the motor 20 and then to flow
toward an upper space S1 of the casing 10, in particular, toward
the oil separating cap 241.
[0047] The discharge pipe DP for guiding the refrigerant separated
by the oil separating cap 241 to the refrigeration cycle is
connected to another side wall surface of the oil separating cap
241. The discharge pipe DP is then connected to the refrigeration
cycle through the casing 10. An oil recollecting pipe 251 for
guiding oil separated by the oil separating cap 241 to the bottom
of the casing 10 is connected to a lower end of the oil separating
cap 241. An oil recollecting pump 252 for pumping oil separated by
the oil separating cap 241 is located at an outlet of the oil
recollecting pipe 251.
[0048] The oil separating pipe 242 includes an inlet in
communication with the upper space S1 of the casing 10 and an
outlet in communication with the inner space of the oil separating
cap 241. The oil separating pipe 242 may be formed to be curved or
bent, as shown in FIG. 8, such that refrigerant and oil guided into
the oil separating cap 241 are separated from each other while
spirally orbiting together.
[0049] The inlet of the oil recollecting pipe 251, as shown in FIG.
7, is in communication with the lower end of the oil separating cap
241 and then penetrates through the compressing unit 30, thereby
being in communication with the inlet of an oil supplying pump 252.
In this configuration, an oil passage (not shown) for connecting
the oil separating cap 241 to the oil recollecting pipe 251 is
formed through the fixed scroll 31 and the main frame 11.
[0050] The oil recollecting pump 252 may be a trochoid gear pump
having inner gear and outer gear as described above. In particular,
the inner gear may be configured as same as in the aforementioned
embodiments, such as being coupled to the crankshaft 23 of the
motor 20.
[0051] In general, the operation of this exemplary embodiment of
the present invention, the process in which oil is separated from
the refrigerant to be recollected is the same or similar to those
described above, so a detailed explanation thereof will not be
repeated. However, because the oil separating unit 240 is installed
inside the casing 10, the flow direction of the refrigerant and oil
is different from that in the previous embodiments. That is,
refrigerant and oil, after being discharged from the compression
chamber P into the inner space of the guide cover 15, flow to the
lower space S2 via the inlet side fluid passage. Thereafter, the
refrigerant and oil flow to the upper space S1 through the outlet
side fluid passage. The refrigerant and oil are then introduced
into the oil separating cap 241 through the oil separating pipe 242
to orbit inside the oil separating cap 241. Accordingly, the
refrigerant and the oil are separated from each other. Afterwards,
the separated refrigerant then flows to the refrigeration cycle
through the discharge pipe DP whereas the separated oil is
recollected to the oil passage 23 a of the crankshaft 23 through
the oil recollecting pipe 251 by a pumping force of the oil
recollecting pump 252. This process may be continuously repeated as
the crankshaft 23 rotates.
[0052] In still another exemplary embodiment of the present
invention, as shown in FIG. 9, the scroll compressor may be
configured to draw the oil recollecting pipe 251 out of the casing
10 to be then connected to the inside of the casing 10. In this
case, a radiating member (not shown) or a capillary tube (not
shown) for lowering an oil temperature may be provided at the
intermediate portion of the oil recollecting pipe 251. When the oil
recollecting pipe 251 is connected to the casing 10 from the
outside of the casing 10, an outlet of the oil recollecting pipe
251 may be connected to a wall surface of the casing 100 so as to
be in communication with the lower space S2 of the casing 10. An
oil recollecting pump 252 may include an inverter motor as
described above with reference to FIG. 6, and may be located at the
intermediate portion of the oil recollecting pipe 251.
[0053] As a result of one or more of the exemplary embodiments, oil
separated by the oil separator is recollected by the oil
recollecting pump. The recollected oil is mixed with a refrigerant
again, whereby it is allowed to prevent a backflow of such oil into
the compressor. Accordingly, the reduction of the amount of
refrigerant circularly supplied into the refrigeration cycle can be
avoided, thereby preventing a degradation of a cooling capacity of
the compressor beforehand. Also, the simplification of the oil
recollecting unit allows the decrease of manufacturing cost. In
addition, as the driving force of the motor may be used to drive
the oil recollecting pump, the configuration of the compressor can
be further simplified.
[0054] The foregoing embodiments and advantages are merely
exemplary and are not to be construed as limiting the present
disclosure. The present teachings can be readily applied to other
types of apparatuses. This description is intended to be
illustrative, and not to limit the scope of the claims. Many
alternatives, modifications, and variations will be apparent to
those skilled in the art. The features, structures, methods, and
other characteristics of the exemplary embodiments described herein
may be combined in various ways to obtain additional and/or
alternative exemplary embodiments.
[0055] As the present features may be embodied in several forms
without departing from the characteristics thereof, it should also
be understood that the above-described embodiments are not limited
by any of the details of the foregoing description, unless
otherwise specified, but rather should be construed broadly within
its scope as defined in the appended claims, and therefore all
changes and modifications that fall within the metes and bounds of
the claims, or equivalents of such metes and bounds are therefore
intended to be embraced by the appended claims.
* * * * *