U.S. patent application number 11/930515 was filed with the patent office on 2008-07-24 for compressor and oil blocking device therefor.
Invention is credited to Se-Heon Choi, Seon-Woong Hwang, Ki-Tae Jang, Chul-Su JUNG, Myung-Kyun Kiem, Byeong-Chul Lee, Byung-Kil Yoo.
Application Number | 20080175738 11/930515 |
Document ID | / |
Family ID | 39636090 |
Filed Date | 2008-07-24 |
United States Patent
Application |
20080175738 |
Kind Code |
A1 |
JUNG; Chul-Su ; et
al. |
July 24, 2008 |
COMPRESSOR AND OIL BLOCKING DEVICE THEREFOR
Abstract
A compressor and oil blocking device therefor are provided which
are capable of preventing oil from spreading onto, for example, a
balance weight, which are capable of preventing oil from being
excessively sucked into a compression device by a separating device
disposed between a driving motor and the compression device, and
which are capable of constantly maintaining a predetermined amount
of oil in compression chambers regardless of a rotational speed of
the driving motor by directly supplying oil to a bearing surface
and the compression chambers and by easily discharging gas from an
oil drain passage. A trochoid gear pump may be used to smoothly
supply oil to the compression device. Further, a synchronous
reluctance motor may be used to enhance a performance of the
compressor and to expand a driving region of the compressor.
Inventors: |
JUNG; Chul-Su; (Seoul,
KR) ; Kiem; Myung-Kyun; (Seoul, KR) ; Jang;
Ki-Tae; (Seoul, KR) ; Lee; Byeong-Chul;
(Seoul, KR) ; Choi; Se-Heon; (Seoul, KR) ;
Hwang; Seon-Woong; (Seoul, KR) ; Yoo; Byung-Kil;
(Seoul, KR) |
Correspondence
Address: |
KED & ASSOCIATES, LLP
P.O. Box 221200
Chantilly
VA
20153-1200
US
|
Family ID: |
39636090 |
Appl. No.: |
11/930515 |
Filed: |
October 31, 2007 |
Current U.S.
Class: |
418/55.6 |
Current CPC
Class: |
F04C 29/0085 20130101;
F04C 29/026 20130101; F04C 2240/807 20130101; F04C 29/028 20130101;
F04C 29/025 20130101; F04C 23/008 20130101; F04C 18/0215
20130101 |
Class at
Publication: |
418/55.6 |
International
Class: |
F04C 29/02 20060101
F04C029/02; F04C 18/00 20060101 F04C018/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 19, 2007 |
KR |
10-2007-0006267 |
Apr 19, 2007 |
KR |
10-2007-0038514 |
Claims
1. A compressor, comprising: a casing; a compression device having
a compression chamber and configured to receive, compress, and
discharge a refrigerant; and an oil blocking device configured to
block oil from the compression device from spreading onto certain
mechanical parts disposed therebelow, wherein the oil blocking
device comprises a substantially planar blocking plate with at
least one oil flow path adjacent an outer circumference of the
blocking plate.
2. The compressor of claim 1, wherein the at least one oil flow
path comprises at least one oil flow hole disposed in the blocking
plate.
3. The compressor of claim 2, wherein the at least one oil flow
path further comprises a tube in communication with the at least
one oil flow hole.
4. The compressor of claim 1, wherein the at least one oil flow
path comprises at least one channel formed at an outer periphery of
the blocking plate.
5. The compressor of claim 4, wherein the at least one channel is
disposed adjacent the casing and forms an enclosed oil passage
therewith.
6. The compressor of claim 1, further comprising a drive motor
configured to drive the compression device, wherein the certain
mechanical parts comprise a balance weight attached to a rotational
shaft connecting the motor to the compression device.
7. The compressor of claim 6, wherein the compression device
comprises: a fixed scroll; and an orbiting scroll disposed adjacent
thereto to form the compression chamber therebetween.
8. The compressor of claim 7, wherein an oil supply passage is
formed in the rotational shaft through which oil is supplied to the
compression device.
9. The compressor of claim 8, further comprising a pump attached to
the rotational shaft configured to pump oil within the oil supply
passage.
10. The compressor of claim 9, wherein the pump comprises a
trochoid gear pump.
11. The compressor of claim 8, further comprising at least one oil
discharge hole formed in the rotational shaft in communication with
the oil supply passage.
12. The compressor of claim 8, further comprising at least one gas
discharge hole formed in the rotational shaft.
13. The compressor of claim 8, further comprising a main frame
having a bearing surface on which the orbiting scroll is supported,
wherein an oil supply passage is formed in the main frame which is
in communication with the oil supply passage formed in the
rotational shaft.
14. The compressor of claim 1, further comprising an oil supply
pipe formed in the casing configured to allow oil to be supplied or
returned to the compressor therethrough.
15. The compressor of claim 1, further comprising an oil level
checking pipe formed in the casing configured to allow an oil level
in the compressor to be checked.
16. A scroll compressor comprising the compressor of claim 1.
17. A compressor, comprising: a casing; a compression device having
a compression chamber and configured to receive, compress, and
discharge a refrigerant; and an oil blocking device configured to
block oil from the compression device from spreading onto certain
mechanical parts, wherein the oil blocking device comprises a
blocking plate with a plurality of oil directing flanges extending
therefrom.
18. The compressor of claim 17, wherein the plurality of oil
directing flanges comprise at least three oil directing
flanges.
19. The compressor of claim 18, wherein at least three oil
directing flanges are configured to direct oil toward a coil of a
motor that drives the compression device.
20. A scroll compressor comprising the compressor of claim 17.
21. A compressor, comprising: a casing; a drive motor disposed
within the casing; a compression device having a fixed scroll and
an orbiting scroll forming a compression chamber therebetween and
driven by the drive motor via a rotational shaft to receive,
compress, and discharge a refrigerant, the orbiting shaft being
supported on a bearing surface of a main frame; a first oil passage
formed in the rotational shaft to supply oil to the compression
device; a second oil passage formed in the main frame in
communication with the first oil passage to supply oil to the
compression device; and an oil blocking device configured to block
oil from spreading onto certain mechanical parts disposed below the
drive motor.
22. The compressor of claim 21, wherein the oil blocking device
comprises a substantially planar blocking plate with at least oil
flow path adjacent an outer circumference of the blocking
plate.
23. The compressor of claim 22, wherein the oil flow path comprises
an oil flow hole disposed in blocking plate.
24. The compressor of claim 23, wherein the oil flow path further
comprises a tube in communication with the oil flow hole.
25. The compressor of claim 22, wherein the oil flow path comprises
a channel formed at an outer periphery of the blocking plate.
26. The compressor of claim 25, wherein the channel is disposed
adjacent the casing and forms an enclosed oil passage
therewith.
27. The compressor of claim 21, wherein the oil block device
comprises a blocking plate with a plurality of oil directing
flanges extending therefrom.
28. The compressor of claim 21, further comprising a drive motor
configured to drive the compression device, wherein the certain
mechanical parts comprise a balance weight attached to a rotational
shaft connecting the motor to the compression device.
29. The compressor of claim 21, further comprising at least one gas
discharge hole formed in the rotational shaft.
30. The compressor of claim 21, further comprising an oil supply
pipe formed in the casing configured to allow oil to be supplied or
returned to the compressor therethrough.
31. The compressor of claim 21, further comprising an oil level
checking pipe formed in the casing configured to allow an oil level
in the compressor to be checked.
32. A scroll compressor comprising the compressor of claim 21.
Description
[0001] The present application claims priority to Korean
Application No. 10-2007-0006267 filed in Korea on Jan. 19, 2007,
and to Korean Application No. 10-2007-0038514 filed in Korea on
Apr. 19, 2007, which are hereby incorporated by reference in their
entirety.
BACKGROUND
[0002] 1. Field
[0003] A compressor and an oil blocking device therefor are
disclosed herein.
[0004] 2. Background
[0005] Compressors are known. However, they suffer from various
disadvantages.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Embodiments will be described in detail with reference to
the following drawings in which like reference numerals refer to
like elements, and wherein:
[0007] FIG. 1 is a longitudinal sectional view of a scroll
compressor according to an embodiment;
[0008] FIG. 2 is a longitudinal sectional view of an oil blocking
device of the scroll compressor of FIG. 1 according to one
embodiment;
[0009] FIG. 3 is a longitudinal sectional view of an oil blocking
device of the scroll compressor of FIG. 1 according to another
embodiment;
[0010] FIG. 4 is a longitudinal sectional view of a separating
device provided in the oil blocking device of FIG. 1;
[0011] FIGS. 5 and 6 are perspective views showing a separating
device provided in the oil blocking device of FIG. 4;
[0012] FIG. 7 is a perspective view of a rotor and a rotation shaft
of a driving motor of FIG. 1;
[0013] FIG. 8 is a perspective view of an oil pump of FIG. 1;
[0014] FIG. 9 is a longitudinal sectional view showing a structure
for supplying oil to a compression chamber of FIG. 1;
[0015] FIG. 10 is a graph showing an energy efficiency ratio (EER)
and an oil circulation rate (OCR) of the compressor of FIG. 1;
and
[0016] FIGS. 12-14 are exemplary installations of a compressor
having an oil blocking device according to embodiments disclosed
herein.
DETAILED DESCRIPTION
[0017] Reference will now be made in detail to embodiments,
examples of which are illustrated in the accompanying drawings.
[0018] Generally, a compressor is a device for converting
mechanical energy into compression energy to compress a fluid.
Compressors are divided into various kinds including a
reciprocating compressor, a rotary compressor, a vane compressor,
and a scroll compressor according to the method for compressing a
fluid.
[0019] A scroll compressor may be provided with a driving motor
that generates a driving force in a hermetic casing, and a
compression device that compresses a refrigerant by receiving the
driving force generated by the driving motor. The compression
device may include an orbiting scroll coupled to a driving or
rotational shaft of the driving motor that performs an orbit motion
with respect to a fixed scroll to form a pair of compression
chambers. As the compression chambers move towards a center, a
refrigerant is consecutively compressed and then discharged.
[0020] When the driving motor rotates, oil contained in the inner
space of the casing is sucked along the driving shaft to lubricate
the compression device and cool the driving motor. However, such
scroll compressors, when the driving motor rotates at a low speed,
a pumping force for the oil is weak and vapor in the oil blocks an
oil passage in the rotational shaft. Accordingly, an amount of oil
supplied to the compression chambers is decreased increasing
friction between the fixed scroll and the orbiting scroll. On the
other hand, when the driving motor rotates at a high speed, an
amount of spread oil is increased, supplying a large amount of oil
to the compression chambers along with the refrigerant.
Accordingly, a leakage amount of oil is increased, lowering
reliability of the compressor. Also, as an amount of the supplied
oil increases, a suction amount of the refrigerant decreases,
lowering the reliability of the compressor.
[0021] Hereinafter, a scroll compressor and oil blocking device
therefor according to embodiments will be explained in detail.
Embodiments are disclosed herein implemented in a scroll
compressor. However, embodiments may be implemented in other type
compressors as well. Further, the scroll compressor may be a high
side type scroll compressor or a low side type compressor.
[0022] As shown in FIG. 1, the scroll compressor 1 may include a
casing 10 hermetically formed so as to contain oil therein, and to
which a refrigerant suction pipe SP and a refrigerant discharge
pipe DP may be connected, a driving motor 20 disposed in the casing
10 that generates a rotational force, and a compression device 30
disposed in the casing 10 that compresses a refrigerant by
receiving the rotational force by from the driving motor 20.
[0023] The casing 10 may include a body 11, which may have having a
cylindrical shape. The driving motor 20 and the compression device
30 may be installed at upper and lower portions of an inner
circumferential surface of the casing 10. The casing 10 may further
include an upper cap 12 and a lower cap 13 that hermetically cover
upper and lower sides of the body 11.
[0024] A main frame 14 and a sub-frame 15 having axial holes 14a
and 15a that support a rotational shaft 23 of the driving motor 20,
respectively, may be fixed to upper and lower sides of the body 11.
An oil level pipe 16a and an oil collecting pipe 16b, which each
may be connected to a refrigerating cycle system, and that
maintaining a predetermined amount of oil may be communicated with
a lower portion of the body 11. The oil collecting pipe 16b may be
positioned to be lower than the oil level pipe 16a.
[0025] The main frame 14 may include an axial hole 14a
penetratingly formed at a center thereof, an oil pocket 14b, which
may be disposed on an upper end of the axial hole 14a to collect
oil sucked through the rotational shaft 23, an oil collecting hole
14c, which may be disposed at one side on an outer circumferential
surface of the oil pocket 14b to collect the oil inside the oil
pocket 14b to the casing 10, and an oil supplying hole 14d, which
may be disposed at another side on the outer circumferential
surface of the oil pocket 14b to partially supply the oil inside
the oil pocket 14b to the compression chambers P. An oil blocking
device or unit 17 that prevents oil from spreading onto a balance
weight 24 by receiving the axial hole 14a may be disposed adjacent
a lower surface of the main frame 14.
[0026] The oil blocking device 17 may have a cylindrical shape, as
shown in FIG. 2, or may have a conical shape having a section
downwardly extending, as shown in FIG. 3. Further, the oil blocking
device 17 may be formed to have an area wide enough to receive
certain mechanical parts, such as balance weight 24, so as to
prevent oil from spreading there onto. The oil blocking device 17
may be formed to have an area wide enough to receive a coil 21a of
a stator 21, or an area wide enough to overlap with the coil 21a in
a vertical direction so that oil collected by contacting the oil
blocking device 17 may be directly supplied onto the coil 21a in
drop form. As shown in FIG. 3, one or more oil guiding portions 17a
may extend from a lower surface of the oil blocking device 17 to
supply collected oil onto the coil 21a.
[0027] A separating device 18 that separates the driving motor 20
and the compression device 30 may be provided on the outer
circumference of the oil blocking device 17, which may be disc
shaped. As shown in FIG. 4, the separating device 18 may be formed
so that an inner circumferential surface thereof may be integrally
extended from an upper outer circumferential surface of the oil
blocking device 17, or so that an outer circumferential surface
thereof may be adhered to an inner circumferential surface of the
casing 10. Accordingly, oil inside the driving motor 20 may be
prevented from being introduced into the compression chambers. An
oil drain passage 18a through which oil supplied to the compression
device 30 may be drained to the driving motor 20 may be concavely
formed at one side on an outer circumferential surface of the
separating device 18. An oil drain guide member 19 disposed towards
a lower side of the casing 10 may be connected to the oil drain
passage 18a, thereby preventing oil drained from the compression
device 30 from spreading in the casing 10.
[0028] As shown in FIG. 5, the oil drain guide member 19 may have a
-shaped sectional surface, and may be coupled to the casing 10 by,
for example, welding so that an opening thereof may form the oil
drain path 19a together with an inner circumferential surface of
the casing 10. The oil drain guide member 19 may be formed to be
tapered so that oil collected through the oil drain passage 18a may
be smoothly drained. Also, an outlet of the oil drain guide member
19 may extend lower than an upper end of the coil 21a of the
driving motor 20 so that drained oil may be prevented from being
mixed with spread oil or refrigerant.
[0029] As shown in FIG. 6, the oil drain guide member 19 may be
formed in a pipe shape. The oil drain passage 18a may be a hole,
not a groove, so as to be tightly coupled to the oil drain guide
member 19.
[0030] A refrigerant passage 18b that passes a refrigerant by
connecting upper and lower sides of the casing 10 to each other on
the basis of the separating device 18 may be formed at another side
on the outer circumferential surface of the separating device 18.
An oil separating plate (not shown) that separates oil from
refrigerant sucked through the suction pipe SP may be inserted or
communicated to/with the refrigerant passage 18b. The refrigerant
passage 18b may be formed in a lower pressure type scroll
compressor where the inner space of the casing 10 is filled with
suction pressure, but may not be formed in a higher pressure type
scroll compressor where the inner space of the casing 10 is filled
with discharge pressure.
[0031] When the separating device 18 is provided with the oil
blocking device 17, an oil drain guide passage (not shown) through
which oil discharged from a discharge port 31c of the fixed scroll
31 together with a refrigerant may be guided to the oil drain
passage 18a may be formed in the main frame 14 or the fixed scroll
31.
[0032] As shown in FIG. 1, the driving motor 20 may include a
stator 21 fixed to the casing 10 that receives power from outside,
a rotor 22 disposed in the stator 21 with a predetermined air gap
therebetween and rotate by being interworked with the stator 21,
and a rotational shaft 23 coupled to the rotor 22 by, for example,
shrinkage fit to transmit a rotational force generated by the
driving motor 20 to the compression device 30.
[0033] As shown in FIGS. 1 to 7, the rotor 22 may be provided with
an axial hole 22a that receives the rotational shaft 23 at a center
thereof. The rotor 22 may be a cylindrical rotor laminator formed
as a plurality of thin steel plates laminated in a shaft lengthwise
direction by, for example, shrinkage fit. A plurality of magnetic
flux barriers 22b, which may be arc-shaped, may be penetratingly
formed in a radial direction of the axial hole 22a along a
circumferential direction of the rotor 22.
[0034] One or more oil collecting grooves 22c that enhance a heat
emitting effect by passing collected oil into the rotor 22 may be
formed on a circumferential surface of the axial hole 22a. The oil
collecting grooves 22c may be formed in a shaft lengthwise
direction, or in a direction inclined from a central longitudinal
axis of the shaft. When being slantingly formed, the oil collecting
groove 22c may be formed in a rotational direction of the
rotational shaft 23 so as to smoothly collect oil.
[0035] The rotational shaft 23 may be provided with an oil passage
23a therein penetratingly formed in a shaft lengthwise direction.
Oil passing holes 23b through which sucked oil may be supplied to
the axial holes 14a and 15a of the main frame 14 and the sub-frame
15 may be formed in a radial direction at upper and lower sides of
the oil passage 23a. One or more gas discharge holes 23c through
which gas sucked through the oil passage 23a together with oil may
be discharged outside the oil passage 23a may be formed between the
oil passing holes 23b.
[0036] As shown in FIG. 1, the gas discharge hole 23c may be
disposed at a lower side of the balance weight 24, thereby being
prevented from being blocked by the balance weight 24 coupled to
the rotational shaft 23. Also, the gas discharge hole 23c may be
disposed inside the oil blocking device 17 so that oil leaked
through the gas discharge hole 23c may be blocked by the oil
blocking device 17.
[0037] As shown in FIG. 1, an oil pump 25 that pumps oil inside the
casing 10 may be disposed at a lower end of the rotational shaft
23. The oil pump 25 may be a trochoid gear pump that forms a
capacity by an inner gear 25a and an outer gear 25b applied so as
to reduce time during which oil supply is stopped due to a suction
pressure change and a liquid refrigerant vaporization.
[0038] A pump driving device 23e coupled to the inner gear 25a of
the trochoid gear pump may be integrally formed at a lower end of
the rotational shaft 23. A driving surface 23f that rotates the
inner gear 25a by being engaged with the inner gear 25a may be
disposed on an outer circumferential surface of the pump driving
device 23e.
[0039] As shown in FIG. 8, the trochoid gear pump may include the
inner gear 25a, the outer gear 25b, a pump cover 25c, and a mesh
box 25d. A thrust plate 25e may be installed between the rotational
shaft 23 and the oil pump 25. The thrust plate 25e may be fixed to
a through hole 15b of the sub frame 15.
[0040] The trochoid gear pump may have a plurality of inlets with
height differences so that a predetermined amount of oil may always
be pumped regardless of a mixed degree between oil and refrigerant.
For instance, when oil and refrigerant are mixed with each other at
an acceptable state, both the oil and the refrigerant are pumped
through both inlets. On the contrary, when the refrigerant and the
oil are mixed with each other at an inferior state in which the
refrigerant is disposed below the oil, only the refrigerant may be
pumped through an inlet disposed at a lower side resulting in oil
deficiency. However, if the inlets are disposed with height
differences, the oil disposed at an upper side may be pumped
together with the refrigerant, thus enhancing a lubricating
performance.
[0041] As shown in FIG. 1, the compression device 30 may include a
fixed scroll 31 fixed to an upper surface of the main frame 14, an
orbiting scroll 32 orbitably disposed on the upper surface of the
main frame 14 so as to form a plurality of compression chambers P
by being engaged with the fixed scroll 31, and an Oldham's ring 33
disposed between the orbiting scroll 32 and the main frame 14 that
orbits the orbiting scroll 32 and prevents the orbiting scroll 32
from rotating about its central axis. The compression device 30 may
further include a high-low pressure separating plate 34 disposed on
a rear surface of a plate portion 31d of the fixed scroll 31 that
divides an inside of the casing 10 into a suction space S1 and a
discharge space S2, and a backflow preventing valve 35 that
prevents backflow of discharge gas by opening and closing the
discharge port 31c of the fixed scroll 31. The fixed scroll 31 may
be formed so that a fixed wrap 31a that forms the compression
chambers P may have an involute shape at a lower surface of the
plate portion 31d. A suction port 31b that communicates with the
suction space S1 of the casing 10 may be formed at a side surface
of the plate portion 31d. The discharge port 31c through which a
compressed refrigerant may be discharged to the discharge space S2
may be formed at a center of an upper surface of the plate portion
31d.
[0042] The orbiting scroll 32 may be formed so that an orbiting
wrap 32a forming the pair of compression chambers P together with
the fixed wrap 31a of the fixed scroll 31 may have an involute
shape at an upper surface of the plate portion 31d of the orbiting
scroll 32. A boss portion 32b coupled to the rotational shaft 23
and receiving a rotational force generated by the driving motor 20
may be formed at a center of the lower surface of the plate portion
32d.
[0043] As shown in FIG. 9, an oil injecting hole 32c that
communicates with the oil supplying hole 14d of the main frame 14
to spray oil supplied through the oil supplying hole 14d to the
compression chambers P may be formed at the plate portion 32d of
the orbiting scroll 32. The oil injecting hole 32c may be formed
before the orbiting wrap 32a starts a compression operation so as
to prevent a refrigerant leakage therethrough. An oil storing
groove 14e that stores a predetermined amount of oil may be formed
at an end of the oil supplying hole 14d of the main frame 14 so
that oil may be smoothly supplied through the oil injecting hole
32c.
[0044] Operation of a scroll compressor according to an embodiment
disclosed herein will be explained herein below.
[0045] When power is supplied to the driving motor 20, the
rotational shaft 23 rotates together with the rotor 22 to transmit
a rotational force to the orbiting scroll 32. Then, the orbiting
scroll 32 performs an orbiting motion on an upper surface of the
main frame 14 due to the Oldham's ring 33 by an eccentric distance.
Accordingly, the compression chambers P that consecutively move are
formed between the fixing wrap 31b of the fixed scroll 31 and the
orbiting wrap 32b of the orbiting scroll 32. As the orbiting scroll
32 continuously performs the orbiting motion, the compression
chambers P move towards the center thus to have a decreased volume,
thereby compressing a sucked refrigerant. Then, the compressed
refrigerant is discharged to the discharge space S2 of the casing
10 through the discharge port 31c of the fixed scroll 31, to the
refrigerating cycle system through the refrigerant discharge pipe
DP, and the above processes are repeated.
[0046] The trochoid gear pump 25 disposed at a lower side of the
rotational shaft 23 pumps oil contained in the casing 10 using a
capacity formed between the inner gear 25a and the outer gear 25b
thereof. Then, the oil is sucked to an upper end of the rotational
shaft 23 through the oil passage 23a. Some of the oil is supplied
to the axial holes 14a and 15a of the main frame 14 and the sub
frame 15 through the oil passage holes 23b, and the other is spread
from the upper end of the rotational shaft 23. Then, the oil spread
from the upper end of the rotational shaft 23 is stored in the oil
pocket 14b of the main frame 14. Some of the oil is collected in
the oil collecting hole 14c of the casing 10, and the other is
moved to a thrust bearing surface of the main frame 14 through the
oil supplying hole 14d to be supplied to the compression chambers P
through the oil injecting hole 32c of the orbiting scroll 32.
[0047] While the rotational shaft 23 rotates or the trochoid gear
pump pumps oil, foam generated from the oil may be introduced into
the oil passage 23a, preventing the oil from being sucked to the
compressor. However, the gas is discharged from the oil passage 23a
through the gas discharge hole 23c disposed in the middle portion
of the rotational shaft 23. Accordingly, the oil may be smoothly
supplied or sucked to the compressor.
[0048] Oil collected after being used to lubricate the axial hole
14a of the main frame 14 may be spread by being stirred by the
balance weight 24. However, the oil is not spread into the casing
10 by the oil blocking device 17 disposed at a lower surface of the
main frame 14, and then is separated from refrigerant and
collected. The collected oil is supplied to the coil 21a of the
stator 21 by the oil blocking device 17 or the oil guiding portion
17a of the oil blocking device 17, thereby cooling the coil 21a. As
shown in FIG. 4, when the separating device 18 is further provided
at the oil blocking device 17, oil spread from the inner space of
the casing 10 is not easily moved to the compression device 30 from
the driving motor 20 due to the separating device 18. The oil is
constantly supplied to the compression chambers P or between the
main frame 14 and the orbiting scroll 32 from the oil pocket 14b of
the main frame 14 through the oil supplying hole 14d and the oil
injecting hole 32c of the orbiting scroll 32.
[0049] Accordingly, when the driving motor is rotated at a high
speed, oil is prevented from being excessively supplied to the
compression chamber of the compression device. As a result, an
amount of a refrigerant sucked to the compression chamber is
increased, enhancing efficiency of the compressor.
[0050] Also, even when the driving motor is rotated at a low speed,
an amount of oil supplied to the compression chamber through the
oil supplying hole and the oil injecting hole may always be
constant. Accordingly, abrasion of the fixed scroll and the
orbiting scroll due to oil deficiency may be prevented, and a
performance of the compressor enhanced by reducing frictional loss.
When the rotational shaft of the driving motor is rotated at a high
speed, oil stirred by the balance weight may be prevented from
spreading by the oil blocking device. Accordingly, oil mixed with
refrigerant may be prevented from being excessively introduced into
the compression chamber. As a result, an amount of oil leaked to
the refrigerating cycle system together with compressed refrigerant
may be reduced, thereby preventing reduced performance of the
compressor due to oil deficiency.
[0051] FIG. 10 is a graph showing an energy efficiency ratio (EER)
and an oil circulation rate (OCR) of the compressor of FIG. 1
according to whether the oil blocking device is provided or not.
Referring to FIG. 10, the compressor having the oil blocking device
has a higher EER than the compressor not having the oil blocking
device by 0.5.about.0.6, and shows a low oil circulation rate than
that of the compressor not having the oil blocking device by
approximately 12.about.13 wt %. The effects become more distinct
when the compressor is rotated at a high speed of more than 60
Hz.
[0052] Since the driving motor may be implemented as a synchronous
reluctance motor, the compressor may have an enhanced performance
when rotated at a low speed. Herein, a heat emitting amount of the
motor may be decreased, expanding a driving region of the
compressor.
[0053] Further, since the balance weight may be coupled to the
rotational shaft, transformation of the rotational shaft due to an
eccentric load of the driving motor may be prevented. Also, the
eccentric load of the driving motor may be effectively compensated
with a reduced weight of the balance weight.
[0054] Since a trochoid gear pump may be used as the oil pump, time
during which oil supply is stopped due to a suction pressure change
and a liquid refrigerant vaporization may be reduced. Also, the
trochoid gear pump may be directly coupled to the rotational shaft,
reducing the number of components and assembly processes.
[0055] Embodiments disclosed herein provide a scroll compressor
capable of always maintaining a predetermined amount of oil
regardless of a rotational speed of a driving motor.
[0056] In accordance with an embodiment broadly described herein,
there is provided a scroll compressor that includes a casing having
a hermetic inner space for contain oil therein a driving motor
disposed at the inner space of the casing a compression device or
unit coupled to a rotational shaft of the driving motor, disposed
at the inner space of the casing, and forming a compression chamber
as a fixing scroll and an orbiting scroll are engaged to each
other, a frame fixedly disposed between the driving motor and the
compression unit, for supporting the rotational shaft of the
driving motor and the compression unit, an oil blocking device or
unit disposed between the driving motor and the compression unit,
for preventing oil from being introduced into the compression
chamber, and an oil supplying device or unit for supplying oil
sucked through the rotational shaft to the compression chamber.
[0057] In accordance with another embodiment broadly described
herein, there is provided a scroll compressor that includes a
casing having a hermetic inner space for containing oil therein, a
driving motor disposed at the inner space of the casing, and having
a rotational shaft to which a balance weight is integrally coupled
and a compression device or unit coupled to the rotational shaft of
the driving motor, disposed at the inner space of the casing, and
forming a compression chamber as a fixing scroll and an orbiting
scroll are engaged to each other. An oil passage may be
penetratingly formed in the rotational shaft in a shaft direction,
and one or more gas discharge holes may be penetratingly formed in
the middle of the oil passage in a radial direction.
[0058] Although an exemplary scroll compressor is presented herein,
for ease of discussion, it is well understood that this can be
equally applied to other types of compressors, or another
application in which this type of oil blocking is required and/or
advantageous.
[0059] More specifically, the compressor and oil blocking device
therefor according to embodiments disclosed herein has numerous
applications in which compression of fluid is required, and in
different types of compressors. Such applications may include, for
example, air conditioning and refrigeration applications. One such
exemplary application is shown in FIG. 12, in which a compressor
710 having an oil blocking device according to embodiments
disclosed herein is installed in a refrigerator/freezer 700.
Installation and functionality of a compressor in a refrigerator is
discussed in detail in U.S. Pat. Nos. 7,082,776, 6,955,064,
7,114,345, 7,055,338, and 6,772,601, the entirety of which are
incorporated herein by reference.
[0060] Another such exemplary application is shown in FIG. 13, in
which a compressor 810 having an oil blocking device according to
embodiments disclosed herein is installed in an outdoor unit of an
air conditioner 800. Installation and functionality of a compressor
in a refrigerator is discussed in detail in U.S. Pat. Nos.
7,121,106, 6,868,681, 5,775,120, 6,374,492, 6,962,058, 6,951,628,
and 5,947,373, the entirety of which are incorporated herein by
reference.
[0061] Another such exemplary application is shown in FIG. 14, in
which a compressor 910 having an oil blocking device according to
embodiments disclosed herein is installed in a single, integrated
air conditioning unit 900. Installation and functionality of a
compressor in a refrigerator is discussed in detail in U.S. Pat.
Nos. 7,032,404, 6,412,298, 7,036,331, 6,588,228, 6,182,460, and
5,775,123, the entirety of which are incorporated herein by
reference.
[0062] 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.
[0063] 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, various
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.
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