U.S. patent application number 14/661228 was filed with the patent office on 2015-12-31 for linear compressor and refrigerator including a linear compressor.
This patent application is currently assigned to LG Electronics Inc.. The applicant listed for this patent is LG ELECTRONICS INC.. Invention is credited to Youngcheol Han, Donghan Kim, Kyeongweon LEE.
Application Number | 20150377531 14/661228 |
Document ID | / |
Family ID | 53039757 |
Filed Date | 2015-12-31 |
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United States Patent
Application |
20150377531 |
Kind Code |
A1 |
LEE; Kyeongweon ; et
al. |
December 31, 2015 |
LINEAR COMPRESSOR AND REFRIGERATOR INCLUDING A LINEAR
COMPRESSOR
Abstract
A linear compressor and a refrigerator including a linear
compressor is provided. The linear compressor may include a shell
including a suction inlet, a cylinder provided in the shell to
define a compression space for a refrigerant, a piston reciprocated
in an axial direction within the cylinder, a discharge valve
provided at one side of the cylinder to selectively discharge the
refrigerant compressed in the compression space, at least one
nozzle disposed in the cylinder to introduce at least a portion of
the refrigerant discharged through the discharge valve into the
cylinder, and at least one filter provided in the shell. The at
least one filter may be disposed in a refrigerant passage defined
from the suction inlet to the at least one nozzle via the discharge
valve. Foreign substances or oil contained in the refrigerant
introduced into the at least one nozzle may be filtered while
passing through the at least one filter.
Inventors: |
LEE; Kyeongweon; (Seoul,
KR) ; Kim; Donghan; (Seoul, KR) ; Han;
Youngcheol; (Seoul, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LG ELECTRONICS INC. |
Seoul |
|
KR |
|
|
Assignee: |
LG Electronics Inc.
|
Family ID: |
53039757 |
Appl. No.: |
14/661228 |
Filed: |
March 18, 2015 |
Current U.S.
Class: |
62/473 ; 417/312;
417/437 |
Current CPC
Class: |
F04B 53/14 20130101;
F04B 39/12 20130101; F04B 39/16 20130101; F04B 37/00 20130101; F04B
39/0038 20130101; F04B 39/0088 20130101; F04B 39/122 20130101; F04B
53/20 20130101; F04B 35/045 20130101; F25B 43/003 20130101; F25B
43/02 20130101; F04B 53/10 20130101; F04B 39/041 20130101; F04B
39/0292 20130101; F04B 39/0027 20130101 |
International
Class: |
F25B 43/00 20060101
F25B043/00; F04B 37/00 20060101 F04B037/00; F04B 39/16 20060101
F04B039/16; F04B 53/10 20060101 F04B053/10; F04B 53/14 20060101
F04B053/14; F04B 39/12 20060101 F04B039/12; F25B 43/02 20060101
F25B043/02; F04B 39/00 20060101 F04B039/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 26, 2014 |
KR |
10-2014-0078763 |
Claims
1. A linear compressor, comprising: a shell comprising a suction
inlet; a cylinder provided in the shell to define a compression
space for a refrigerant; a piston reciprocated in an axial
direction within the cylinder; a discharge valve provided at one
end of the cylinder to selectively discharge the refrigerant
compressed in the compression space; at least one nozzle disposed
in the cylinder to introduce at least a portion of the refrigerant
discharged through the discharge valve into the cylinder; and at
least one filter provided in the shell, wherein the at least one
filter is installed in a refrigerant passage that extends from the
suction inlet to the at least one nozzle via the discharge valve,
and wherein foreign substances or oil contained in the refrigerant
to be introduced into the at least one nozzle are filtered while
passing through the at least one filter.
2. The linear compressor according to claim 1, further comprising a
suction muffler provided in the shell to reduce noise of the
refrigerant suctioned in through the suction inlet, wherein the at
least one filter comprises a filter installed in the suction
muffler.
3. The linear compressor according to claim 2, wherein the suction
muffler comprises a first muffler and a second muffler, and wherein
the filter is installed between the first muffler and the second
muffler.
4. The linear compressor according to claim 3, further comprising:
a groove formed in one of the first muffler or the second muffler;
and a protrusion provided at the other one of the first muffler or
the second muffler, wherein the protrusion is coupled to the
groove, and wherein the filter is interposed between the groove and
the protrusion.
5. The linear compressor according to claim 2, wherein the filter
comprises a magnetic member.
6. The linear compressor according to claim 2, wherein the filter
is formed of a stainless steel material.
7. The linear compressor according to claim 1, further comprising a
frame installed to an outside of the cylinder, wherein the at least
one filter comprises a filter installed in a space between the
cylinder and the frame.
8. The linear compressor according to claim 7, wherein the cylinder
comprises a cylinder body and a cylinder flange that extends in a
radial direction of the cylinder body, and wherein the frame
comprises a recess in which the cylinder flange is inserted, and a
seat, on which a surface of the cylinder flange is seated.
9. The linear compressor according to claim 8, wherein the filter
is positioned on the seat of the frame.
10. The linear compressor according to claim 8, wherein the filter
is positioned between an outer circumferential surface of the
cylinder flange and an inner circumferential surface of the
recess.
11. The linear compressor according to claim 7, wherein the filter
has a ring shape.
12. The linear compressor according to claim 7, wherein the filter
comprises a felt formed of polyethylene terephthalate (PET)
fiber.
13. The linear compressor according to claim 1, further comprising
at least one gas inflow recessed from an outer circumferential
surface of the cylinder to communicate with the at least one
nozzle, wherein the at least one filter comprises a filter
installed in the at least one gas inflow.
14. The linear compressor according to claim 13, wherein the filter
comprises a thread having a predetermined thickness or
diameter.
15. The linear compressor according to claim 14, wherein the thread
is formed of a polyethylene terephthalate (PET) material.
16. The linear compressor according to claim 14, wherein the thread
is wound several times around the at least one gas inflow.
17. A refrigerator, comprising: a linear compressor comprising a
reciprocating piston and a cylinder that accommodates the piston
and having an outer circumferential surface through which a
refrigerant is introduced; at least one filter provided in the
linear compressor to filter the refrigerant introduced through the
outer circumferential surface of the cylinder; a condenser that
condenses the refrigerant compressed in the linear compressor; and
a dryer to remove foreign substances or oil contained in the
refrigerant condensed in the condenser, wherein the dryer comprises
an adsorbent to adsorb the oil contained in the refrigerant.
18. The refrigerator according to claim 17, wherein the adsorbent
comprises a molecular sieve provided with a plurality of holes to
adsorb the oil, the adsorbent having a grain shape.
19. The refrigerator according to claim 17, wherein the adsorbent
comprises an oil adsorbent paper or felt.
20. The refrigerator according to claim 17, wherein the dryer
comprises: a first dryer filter disposed within an inlet-side of
the dryer; a second dryer filter supported by the first dryer
filter, the second dryer filter comprising the adsorbent; and a
third dryer filter that supports the second dryer, the third dryer
filter being disposed within an outlet-side of the dryer.
21. The refrigerator according to claim 17, wherein the at least
one filter comprises a filter installed at a suction muffler that
reduces flow noise of the refrigerant suctioned into the linear
compressor.
22. The refrigerator according to claim 17, wherein the at least
one filter comprises a filter disposed at one end of the cylinder
to filter at least a portion of the refrigerant discharged from the
cylinder.
23. The refrigerator according to claim 17, wherein the at least
one filter comprises a filter wound around the outer
circumferential surface of the cylinder.
24. A linear compressor, comprising: a shell comprising a suction
inlet; a cylinder provided in the shell to define a compression
space for a refrigerant; a piston reciprocated in an axial
direction within the cylinder; a discharge valve provided at one
end of the cylinder to selectively discharge the refrigerant
compressed in the compression space; at least one nozzle disposed
in the cylinder to introduce at least a portion of the refrigerant
discharged through the discharge valve into the cylinder; and a
plurality of filters installed along a refrigerant passage that
extends from the suction inlet to the at least one nozzle via the
discharge valve, wherein foreign substances or oil contained in the
refrigerant to be introduced into the at least one nozzle are
filtered while passing through the plurality of filters.
25. The linear compressor according to claim 24, wherein the
plurality of filters comprises a first filter installed in a
suction muffler provided in the shell to reduce noise of the
refrigerant suctioned in through the suction inlet.
26. The linear compressor according to claim 25, wherein the
suction muffler comprises a first muffler and a second muffler, and
wherein the filter is installed between the first muffler and the
second muffler.
27. The linear compressor according to claim 25, wherein the
plurality of filters further comprises a second filter installed
between the cylinder and a frame installed at an outside of the
cylinder.
28. The linear compressor according to claim 27, wherein the
cylinder comprises a cylinder body and a cylinder flange that
extends in a radial direction of the cylinder body, and wherein the
frame comprises a recess in which the cylinder flange is inserted,
and a seat, on which a surface of the cylinder flange is seated,
and wherein the second filter is positioned on the seat of the
frame.
29. The linear compressor according to claim 27, further comprising
at least one gas inflow recessed from an outer circumferential
surface of the cylinder to communicate with the at least one
nozzle, wherein the plurality of filters further comprises a third
filter installed in the at least one gas inflow.
30. The linear compressor according to claim 29, wherein the filter
comprises a thread having a predetermined thickness or diameter.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims priority under 35 U.S.C. .sctn.119
to Korean Application No. 10-2014-0078763, filed in Korea on Jun.
26, 2014, whose entire disclosure is hereby incorporated by
reference.
BACKGROUND
[0002] 1. Field
[0003] A linear compressor and a refrigerator including a linear
compressor are disclosed herein.
[0004] 2. Background
[0005] In general, compressors are machines that receive power from
a power generation device, such as an electric motor or turbine, to
compress air, a refrigerant, or various working gases, thereby
increasing in pressure. Compressors are being widely used in home
appliances, such as refrigerators or air conditioners, or
industrial fields.
[0006] Compressors may be largely classified into reciprocating
compressors, in which a compression space into and from which a
working gas is suctioned and discharged, is defined between a
piston and a cylinder to allow the piston to be linearly
reciprocated in the cylinder, thereby compressing the working gas;
rotary compressors, in which a compression space into and from
which a working gas is suctioned or discharged, is defined between
a roller that eccentrically rotates and a cylinder to allow the
roller to eccentrically rotate along an inner wall of the cylinder,
thereby compressing the working gas; and scroll compressors, in
which a compression space into and from which a working gas is
suctioned and discharged, is defined between an orbiting scroll and
a fixed scroll to compress the working gas while the orbiting
scroll rotates along the fixed scroll. In recent years, a linear
compressor, which is directly connected to a drive motor and in
which a piston is linearly reciprocated, to improve compression
efficiency without mechanical loss due to movement conversion and
having a simple structure, is being widely developed. The linear
compressor may suction and compress a working gas, such as a
refrigerant, while the piston is linearly reciprocated in a sealed
shell by a linear motor and then discharge the working gas.
[0007] The linear motor is configured to allow a permanent magnet
to be disposed between an inner stator and an outer stator. The
permanent magnet may be linearly reciprocated by an electromagnetic
force between the permanent magnet and the inner (or outer) stator.
Also, as the permanent magnet operates in a state in which the
permanent magnet is connected to the piston, the refrigerant may
suctioned and compressed while the piston is linearly reciprocated
within the cylinder, and then, may be discharged.
[0008] The present Applicant has filed for a patent (hereinafter,
referred to as a "prior art document") and then registered the
patent with respect to the linear compressor, as Korean Patent No.
10-1307688, filed in Korea on Sep. 5, 2013, and entitled "linear
compressor", which is hereby incorporated by reference. The linear
compressor according to the prior art document includes a shell to
accommodate a plurality of components. A vertical height of the
shell may be somewhat high, as illustrated in the prior art
document. An oil supply assembly to supply oil between a cylinder
and a piston may be disposed within the shell. When the linear
compressor is provided in a refrigerator, the linear compressor may
be disposed in a machine room provided at a rear side of the
refrigerator.
[0009] In recent years, a major concern of customers is increasing
an inner storage space of the refrigerator. To increase the inner
storage space of the refrigerator, it may be necessary to reduce a
volume of the machine room. To reduce the volume of the machine
room, it may be important to reduce a size of the linear
compressor.
[0010] However, as the linear compressor disclosed in the prior art
document has a relatively large volume, the linear compressor in
the prior art document is not applicable to a refrigerator, for
which an increase in the inner storage space is sought. To reduce
the size of the linear compressor, it may be necessary to reduce a
size of a main component of the compressor. In this case, the
compressor may deteriorate in performance.
[0011] To compensate for the deteriorated performance of the
compressor, it may be necessary to increase a drive frequency.
However, the more the drive frequency of the compressor is
increased, the more a friction force due to oil circulating in the
compressor is increased, deteriorating performance of the
compressor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Embodiments will be described in detail with reference to
the following drawings in which like reference numerals refer to
like elements, and wherein:
[0013] FIG. 1 is a schematic diagram of a refrigerator according to
an embodiment;
[0014] FIG. 2 is a cross-sectional view of a dryer of the
refrigerator of FIG. 1;
[0015] FIG. 3 is a cross-sectional view of a linear compressor of
the refrigerator of FIG. 1;
[0016] FIG. 4 is a cross-sectional view of a suction muffler of the
linear compressor of FIG. 3;
[0017] FIG. 5 is a view illustrating a state in which a first
filter is coupled to the suction muffler of FIG. 4;
[0018] FIG. 6 is a partial cross-sectional view illustrating a
position of a second filter according to an embodiment;
[0019] FIG. 7 is an exploded perspective view of a cylinder and a
frame of the linear compressor of FIG. 3;
[0020] FIG. 8 is an exploded perspective of the frame of FIG.
7;
[0021] FIG. 9 is a cross-sectional view illustrating a state in
which the cylinder and a piston are coupled to each other according
to an embodiment;
[0022] FIG. 10 is a view of the cylinder according to an
embodiment;
[0023] FIG. 11 is an enlarged cross-sectional view of portion A of
FIG. 9;
[0024] FIG. 12 is a cross-sectional view illustrating a refrigerant
flow in the linear compressor of FIG. 3; and
[0025] FIG. 13 is a cross-sectional view illustrating a position of
a second filter according to another embodiment.
DETAILED DESCRIPTION
[0026] Hereinafter, embodiments will be described with reference to
the accompanying drawings. Embodiments may, however, be embodied in
many different forms and should not be construed as being limited
to the embodiments set forth herein; rather, alternate embodiments
falling within the spirit and scope will fully convey the concept
to those skilled in the art.
[0027] FIG. 1 is a schematic diagram of a refrigerator according to
an embodiment. Referring to FIG. 1, a refrigerator 10 according to
an embodiment may include a plurality of devices to drive a
refrigeration cycle.
[0028] In detail, the refrigerator 10 may include a compressor 100
to compress a refrigerant, a condenser 20 to condense the
refrigerant compressed in the compressor 100, a dryer 200 to remove
moisture, foreign substances, or oil from the refrigerant condensed
in the condenser 20, an expansion device 30 to decompress the
refrigerant having passed through the dryer 200, and an evaporator
40 to evaporate the refrigerant decompressed in the expansion
device 30. The refrigerator 10 may further include a condensation
fan 25 to blow air toward the condenser 20, and an evaporation fan
45 to blow air toward the evaporator 40.
[0029] The compressor 100 may be a linear compressor in which a
piston may be directly connected to a motor to compress the
refrigerant while the piston is linearly reciprocated within a
cylinder. The expansion device 30 may include a capillary tube
having a relatively small diameter.
[0030] A liquid refrigerant condensed in the condenser 20 may be
introduced into the dryer 200. A gaseous refrigerant may be
partially contained in the liquid refrigerant. A filter to filter
the liquid refrigerant introduced into the dryer 200 may be
provided in the dryer 200. Hereinafter, components of the dryer 200
will be described with reference to the accompanying drawings.
[0031] FIG. 2 is a cross-sectional view of a dryer of the
refrigerator of FIG. 1. Referring to FIG. 2, the dryer 200
according to an embodiment may include a dryer body 210 to define a
flow space for the refrigerant, a refrigerant inflow 211 disposed
on or at one or a first side of the dryer body 210 to guide
introduction of the refrigerant, and a refrigerant discharge 215
disposed on or at the other or a second side of the dryer body 210
to guide discharge of the refrigerant. For example, the dryer body
210 may have a long cylindrical shape.
[0032] Dryer filters 220, 230, and 240 may be provided in the dryer
body 210. In detail, the dryer filters 220, 230, and 240 may
include a first dryer filter 220 disposed adjacent to the
refrigerant inflow 211, a third dryer filter 240 spaced apart from
the first dryer filter 220 and disposed adjacent to the refrigerant
discharge 215, and a second dryer filter 230 disposed between the
first dryer filter 220 and the third dryer filter 240.
[0033] The first dryer filter 220 may be disposed adjacent to an
inside of the refrigerant inflow 211, that is, disposed at a
position closer to the refrigerant inflow 211 than the refrigerant
discharge 215.
[0034] The first dryer filter 220 may have an approximately
hemispherical shape. An outer circumferential surface of the first
dryer filter 220 may be coupled to an inner circumferential surface
of the dryer body 210. A plurality of through holes 221 to guide
flow of the refrigerant may be defined in the first dryer filer
220. A foreign substance having a relatively large volume may be
filtered by the first dryer filter 220.
[0035] The second dryer filter 230 may include a plurality of
adsorbents 231. Each of the adsorbents 231 may be a grain having a
predetermined size. The adsorbent 231 may be a molecular sieve and
have a predetermined size of about 5 mm to about 10 mm.
[0036] A plurality of holes may be defined in the adsorbent 231.
Each of the plurality of holes may have a size similar to a size of
oil (about 10 .ANG.). The hole may have a size greater than a size
(about 2.8 .ANG. to about 3.2 .ANG.) of the moisture and (about 4.0
.ANG. in case of R134a, and about 4.3 .ANG. in the case of R600a)
of the refrigerant. The term "oil" may refer to a working oil or
cutting oil injected when components of the refrigeration cycle are
manufactured or processed.
[0037] The refrigerant and moisture passing through the first dryer
filter 220 may be easily discharged even though the refrigerant and
moisture are easily introduced into the plurality of holes while
passing through the adsorbents 231. Thus, the refrigerant and
moisture may not be easily adsorbed onto the adsorbents 231.
However, if the oil is introduced into the plurality of holes, the
oil may not be easily discharged, and thus, may be maintained in a
state in which the oil is adsorbed onto the adsorbents 231.
[0038] For example, the adsorbent 231 may include a BASF 13X
molecular sieve. A hole defined in the BASF 13X molecular sieve may
have a size of about 10 .ANG. (1 nm), and the BASF 13X molecular
sieve may be expressed as a chemical formula: Na2O.Al2O3.mSiO2.nH20
(m.ltoreq.2.35).
[0039] The oil contained in the refrigerant may be adsorbed into
the plurality of adsorbents 231 while passing through the second
dryer filter 230. Alternatively, the second dryer filter 230 may
include an oil adsorbent paper or an adsorbent having a felt,
instead of the plurality of adsorbents each having a grain
shape.
[0040] The third dryer filter 240 may include a coupling portion
241 coupled to the inner circumferential surface of the dryer body
210, and a mesh 242 that extends from the coupling portion 241
toward the refrigerant discharge 215. The third dryer filer 240 may
be a mesh filter. A foreign substance having a fine size contained
in the refrigerant may be filtered by the mesh 242.
[0041] Each of the first dryer filter 220 and the third dryer
filter 240 may serve as a support to locate the plurality of
adsorbents 231 within the dryer body 210. That is, discharge of the
plurality of adsorbents 231 from the dryer 200 may be restricted by
the first and third dryer filters 220 and 240.
[0042] As described above, the filters may be provided in the dryer
200 to remove foreign substances or oil contained in the
refrigerant, thereby improving reliability of the refrigerant that
acts as a gas bearing.
[0043] FIG. 3 is a cross-sectional view of a linear compressor of
the refrigerant in FIG. 1. Referring to FIG. 3, the linear
compressor 100 according to an embodiment may include a shell 101
having an approximately cylindrical shape, a first cover 102
coupled to a first side of the shell 101, and a second cover 103
coupled to a second side of the shell 101. For example, the linear
compressor 100 may be laid out in a horizontal direction. The first
cover 102 may be coupled to a right or first lateral side of the
shell 101, and the second cover 103 may be coupled to a left or
second lateral side of the shell 101 with reference to FIG. 3. Each
of the first and second covers 102 and 103 may be understood as one
component of the shell 101.
[0044] The linear compressor 100 may further include a cylinder 120
provided in the shell 101, a piston 130 linearly reciprocated
within the cylinder 120, and a motor assembly that serves as a
linear motor to apply a drive force to the piston 130. When the
motor assembly 140 operates, the piston 130 may be linearly
reciprocated at a high rate. The linear compressor 100 according to
this embodiment may have a drive frequency of about 100 Hz, for
example.
[0045] The linear compressor 100 may include a suction inlet 104,
through which the refrigerant may be introduced, and a discharge
outlet 105, through which the refrigerant compressed in the
cylinder 120 may be discharged. The suction inlet 104 may be
coupled to the first cover 102, and the discharge outlet 105 may be
coupled to the second cover 103.
[0046] The refrigerant in suctioned through the suction inlet 104
may flow into the piston 130 via a suction muffler 150. Thus, while
the refrigerant passes through the suction muffler 150, noise may
be reduced. The suction muffler 150 may include a first muffler 151
coupled to a second muffler 153. At least a portion of the suction
muffler 150 may be disposed within the piston 130.
[0047] The piston 130 may include a piston body 131 having an
approximately cylindrical shape, and a piston flange 132 that
extends from the piston body 131 in a radial direction. The piston
body 131 may be reciprocated within the cylinder 120, and the
piston flange 132 may be reciprocated outside of the cylinder
120.
[0048] The piston 130 may be formed of an aluminum material, such
as aluminum or an aluminum alloy, which is a nonmagnetic material.
As the piston 130 may be formed of the aluminum material, a
magnetic flux generated in the motor assembly 140 may not be
transmitted into the piston 130, and thus, may be prevented from
leaking outside of the piston 130. The piston 130 may be
manufactured by a forging process, for example.
[0049] The cylinder 120 may be formed of an aluminum material, such
as aluminum or an aluminum alloy, which is a nonmagnetic material.
The cylinder 120 and the piston 130 may have a same material
composition, that is, a same kind of material and composition.
[0050] As the piston cylinder 120 may be formed of the aluminum
material, a magnetic flux generated in the motor assembly 200 may
not be transmitted into the cylinder 120, and thus, may be
prevented from leaking outside of the cylinder 120. The cylinder
120 may be manufactured by an extruding rod processing process, for
example.
[0051] Also, as the piston 130 may be formed of the same material
as the cylinder 120, the piston 130 may have a same thermal
expansion coefficient as the cylinder 120. When the linear
compressor 100 operates, a high-temperature (a temperature of about
100.degree. C.) environment may be created within the shell 100.
Thus, as the piston 130 and the cylinder 120 may have the same
thermal expansion coefficient, the piston 130 and the cylinder 120
may be thermally deformed by a same degree. As a result, the piston
130 and the cylinder 120 may be thermally deformed with sizes and
in directions different from each other to prevent the piston 130
from interfering with the cylinder 120 while the piston 130
moves.
[0052] The cylinder 120 may be configured to accommodate at least a
portion of the suction muffler 150 and at least a portion of the
piston 130. The cylinder 120 may have a compression space P, in
which the refrigerant may be compressed by the piston 130. A
suction hole 133, through which the refrigerant may be introduced
into the compression space P, may be defined in or at a front
portion of the piston 130, and a suction valve 135 to selectively
open the suction hole 133 may be disposed on or at a front side of
the suction hole 133. A coupling hole, to which a predetermined
coupling member may be coupled, may be defined in an approximately
central portion of the suction valve 135.
[0053] A discharge cover 160 that defines a discharge space or
discharge passage for the refrigerant discharged from the
compression space P, and a discharge valve assembly 161, 162, and
163 coupled to the discharge cover 160 to selectively discharge the
refrigerant compressed in the compression space P may be provided
at a front side of the compression space P. The discharge valve
assembly 161, 162, and 163 may include a discharge valve 161 to
introduce the refrigerant into the discharge space of the discharge
cover 160 when a pressure within the compression space P is above a
predetermined discharge pressure, a valve spring 162 disposed
between the discharge valve 161 and the discharge cover 160 to
apply an elastic force in an axial direction, and a stopper 163 to
restrict deformation of the valve spring 162.
[0054] The term "compression space P" may be refer to a space
defined between the suction valve 135 and the discharge valve 161.
The term "axial direction" may refer a direction in which the
piston 130 may be reciprocated, that is, a transverse direction in
FIG. 3. Also, in the axial direction, a direction from the suction
inlet 104 toward the discharge outlet 105, that is, a direction in
which the refrigerant flows, may be referred to as a "frontward
direction", and a direction opposite to the frontward direction may
be referred to as a "rearward direction". On the other hand, the
term "radial direction" may refer to a direction perpendicular to
the direction in which the piston 130 is reciprocated, that is, a
vertical direction in FIG. 3.
[0055] The stopper 163 may be seated on the discharge cover 160,
and the valve spring 162 may be seated at a rear side of the
stopper 163. The discharge valve 161 may be coupled to the valve
spring 162, and a rear portion or rear surface of the discharge
valve 161 may be supported by a front surface of the cylinder 120.
The valve spring 162 may include a plate spring, for example.
[0056] The suction valve 135 may be disposed on or at a first side
of the compression space P, and the discharge valve 161 maybe
disposed on or at a second side of the compression space P, that
is, a side opposite of the suction valve 135.
[0057] While the piston 130 is linearly reciprocated within the
cylinder 120, when the pressure of the compression space P is below
the predetermined discharge pressure and a predetermined suction
pressure, the suction valve 135 may be opened to suction the
refrigerant into the compression space P. On the other hand, when
the pressure of the compression space P is above the predetermined
suction pressure, the refrigerant may be compressed in the
compression space P in a state in which the suction valve 135 is
closed.
[0058] When the pressure of the compression space P is above the
predetermined discharge pressure, the valve spring 162 may be
deformed to open the discharge valve 161. The refrigerant may be
discharged from the compression space P into the discharge space of
the discharge cover 160.
[0059] The refrigerant flowing into the discharge space of the
discharge cover 160 may be introduced into a loop pipe 165. The
loop pipe 165 may be coupled to the discharge cover 160 to extend
to the discharge outlet 105, thereby guiding the compressed
refrigerant in the discharge space into the discharge outlet 105.
For example, the loop pipe 165 may have a shape which is wound in a
predetermined direction and extends in a rounded shape. The loop
pipe 165 may be coupled to the discharge outlet 105.
[0060] The linear compressor 100 may further include a frame 110.
The frame 110 may fix the cylinder 120 and be coupled to the
cylinder 120 by a separate coupling member, for example. The frame
110 may be disposed to surround the cylinder 120. That is, the
cylinder 120 may be accommodated within the frame 110. The
discharge cover 172 may be coupled to a front surface of the frame
110.
[0061] At least a portion of the high-pressure gaseous refrigerant
discharged through the open discharge valve 161 may flow toward an
outer circumferential surface of the cylinder 120 through a space
formed at a portion at which the cylinder 120 and the frame 110 are
coupled to each other. The refrigerant may be introduced into the
cylinder 120 through one or more gas inflow (see reference numeral
122 of FIG. 7) and one or more nozzle (see reference numeral 123 of
FIG. 11), which may be defined in the cylinder 120. The introduced
refrigerant may flow into a space defined between the piston 130
and the cylinder 120 to allow an outer circumferential surface of
the piston 130 to be spaced apart from an inner circumferential
surface of the cylinder 120. Thus, the introduced refrigerant may
serve as a "gas bearing" that reduces friction between the piston
130 and the cylinder 120 while the piston 130 is reciprocated.
[0062] The motor assembly 140 may include outer stators 141, 143,
and 145 fixed to the frame 110 and disposed to surround the
cylinder 120, an inner stator 148 disposed to be spaced inward from
the outer stators 141, 143, and 145, and a permanent magnet 146
disposed in a space between the outer stators 141, 143, and 145 and
the inner stator 148. The permanent magnet 146 may be linearly
reciprocated by a mutual electromagnetic force between the outer
stators 141, 143, and 145 and the inner stator 148. Also, the
permanent magnet 146 may be a single magnet having one polarity, or
a plurality of magnets having three polarities.
[0063] The permanent magnet 146 may be coupled to the piston 130 by
a connection member 138. In detail, the connection member 138 may
be coupled to the piston flange 132 and be bent to extend toward
the permanent magnet 146. As the permanent magnet 146 is
reciprocated, the piston 130 may be reciprocated together with the
permanent magnet 146 in the axial direction.
[0064] The motor assembly 140 may further include a fixing member
147 to fix the permanent magnet 146 to the connection member 138.
The fixing member 147 may be formed of a composition in which glass
fiber or carbon fiber is mixed with a resin. The fixing member 147
may surround an outside of the permanent magnet 146 to firmly
maintain a coupled state between the permanent magnet 146 and the
connection member 138.
[0065] The outer stators 141, 143, and 145 may include coil winding
bodies 143 and 145, and a stator core 141. The coil winding bodies
143 and 145 may include a bobbin 143, and a coil 145 wound in a
circumferential direction of the bobbin 145. The coil 145 may have
a polygonal cross-section, for example, a hexagonal cross-section.
The stator core 141 may be manufactured by stacking a plurality of
laminations in the circumferential direction and be disposed to
surround the coil winding bodies 143 and 145.
[0066] A stator cover 149 may be disposed on or at one side of the
outer stators 141, 143, and 145. A first side of the outer stators
141, 143, and 145 may be supported by the frame 110, and a second
side of the outer stators 141, 143, and 145 may be supported by the
stator cover 149. The inner stator 148 may be fixed to a
circumference of the frame 110. In the inner stator 148, a
plurality of laminations may be stacked in the circumferential
direction outside of the cylinder 120.
[0067] The linear compressor 100 may further include a support 137
to support the piston 130, and a back cover 170 spring-coupled to
the support 137. The support 137 may be coupled to the piston
flange 132 and the connection member 138 by a predetermined
coupling member, for example.
[0068] A suction guide 155 may be coupled to a front portion of the
back cover 170. The suction guide 155 may guide the refrigerant
suctioned in through the suction inlet 104 to introduce the
refrigerant into the suction muffler 150.
[0069] The linear compressor 100 may further include a plurality of
springs 176 which are adjustable in natural frequency to allow the
piston 130 to perform a resonant motion. The plurality of springs
176 may include a first spring supported between the support 137
and the stator cover 149, and a second spring supported between the
support 137 and the back cover 170.
[0070] The linear compressor 100 may additionally further include
plate springs 172 and 174, respectively, disposed on both sides of
the shell 101 to allow inner components of the compressor 100 to be
supported by the shell 101. The plate springs 172 and 174 may
include a first plate spring 172 coupled to the first cover 102,
and a second plate spring 174 coupled to the second cover 103. For
example, the first plate spring 172 may be fitted into a portion at
which the shell 101 and the first cover 102 are coupled to each
other, and the second plate spring 174 may be fitted into a portion
at which the shell 101 and the second cover 103 are coupled to each
other.
[0071] FIG. 4 is a cross-sectional view of a suction muffler of the
linear compressor of FIG. 1. FIG. 5 is a view illustrating a state
in which a first filter is coupled to the suction muffler of FIG.
4.
[0072] Referring to FIGS. 4 and 5, the suction muffler 150
according to this embodiment may include the first muffler 151, the
second muffler 153 coupled to the first muffler 151, and a first
filter 310 supported by the first and second mufflers 151 and 153.
A flow space, in which the refrigerant may flow, may be defined in
each of the first and second mufflers 151 and 153. The first
muffler 151 may extend from an inside of the suction inlet 104 in a
direction of the discharge outlet 105, and at least a portion of
the first muffler 151 may extend inside of the suction guide 155.
The second muffler 153 may extend from the first muffler 151 inside
of the piston body 131.
[0073] The first filter 310 may be disposed in the flow space to
filter foreign substances. The first filter 310 may be formed of a
material having a magnetic property. Thus, foreign substances
contained in the refrigerant, in particular, metallic substances,
may be easily filtered.
[0074] For example, the first filter 310 may be formed of stainless
steel, and thus, may have a magnetic property to prevent the first
filter 310 from rusting. Alternatively, the first filter 310 may be
coated with a magnetic material, or a magnet may be attached to a
surface of the first filter 310.
[0075] The first filter 310 may be provided as a mesh-type
structure having a plurality of filter holes and have an
approximately circular plate shape. Each of the filter holes may
have a diameter or width less than a predetermined diameter or
width, that is, a predetermined size. For example, the
predetermined size may be about 25 .mu.m.
[0076] The first muffler 151 and the second muffler 153 may be
assembled with each other using a press-fit manner, for example.
The first filter 310 may be fitted into a portion into which the
first and second mufflers 151 and 153 are press-fitted and then be
assembled. In detail, a groove 151a, to which at least a portion of
the second muffler 153 may be coupled, may be defined in the first
muffler 151. The second muffler 153 may include a protrusion 153a
inserted into the groove 151a of the first muffler 151.
[0077] The first filter 310 may be supported by the first and
second mufflers 151 and 153 in a state in which both sides of the
first filter 310 are disposed between the groove 151a and the
protrusion 153a. In the state in which the first filter 310 is
disposed between the first and second mufflers 151 and 153, when
the first and second mufflers 151 and 153 move in a direction that
approach each other and then are press-fitted, both sides of the
first filter 310 may be inserted and fixed between the groove 151a
and the protrusion 153a.
[0078] As described above, as the first filter 310 may be provided
on the suction muffler 150, a foreign substance having a size
greater than a predetermined size of the refrigerant suctioned in
through the suction inlet 104 may be filtered by the first filter
310. Thus, the first filter 310 may filter the foreign substance
from the refrigerant acting as the gas bearing between the piston
130 and the cylinder 120 to prevent the foreign substance from
being introduced into the cylinder 120. Also, as the first filter
310 is firmly fixed to the portion at which the first and second
mufflers 151 and 153 are coupled or press-fitted, separation of the
first filter 310 from the suction muffler 150 may be prevented.
[0079] In this embodiment, although the groove 151a is defined in
the first muffler 151, and the protrusion 153a is disposed on the
second muffler 153, embodiments are not limited thereto. For
example, the protrusion 153a may be disposed on the first muffler
151, and the groove 151a may be defined in the second muffler
153.
[0080] FIG. 6 is a partial cross-sectional view illustrating a
position of a second filter according to an embodiment. FIG. 7 is
an exploded perspective view of a cylinder and a frame of the
linear compressor of FIG. 3. FIG. 8 is an exploded perspective of
the frame of FIG. 7.
[0081] Referring to FIGS. 6 to 8, the linear compressor 100
according to an embodiment may include a second filter 320 disposed
between the frame 110 and the cylinder 120 to filter a
high-pressure gas refrigerant discharged through the discharge
valve 161. The second filter 320 may be disposed on or at a portion
of a coupled surface at which the frame 110 and the cylinder 120
are coupled to each other.
[0082] In detail, the cylinder 120 may include a cylinder body 121
having an approximately cylindrical shape, and a cylinder flange
125 that extends from the cylinder body 121 in a radial direction.
The cylinder body 121 may include at least one gas inflow 122,
through which the discharged gas refrigerant may be introduced. The
gas inflow 122 may be formed in a circular shape along a
circumferential surface of the cylinder body 121.
[0083] The at least one gas inflow 122 may include a plurality of
gas inflows 122. The plurality of gas inflows 122 may include gas
inflows (see reference numerals 122a and 122b of FIG. 10) disposed
on a first side with respect to a center or central portion 121c of
the cylinder body 121 in an axial direction, and a gas inflow (see
reference numeral 122c of FIG. 10) disposed on a second side with
respect to the center or central portion 121c of the cylinder body
121 in the axial direction.
[0084] One or more coupling portion 126 coupled to the frame 110
may be disposed on the cylinder flange 125. Each coupling portion
126 may protrude outward from an outer circumferential surface of
the cylinder flange 125, and be coupled to a cylinder coupling hole
118 of the frame 110 by a predetermined coupling member, for
example.
[0085] The cylinder flange 125 may have a seat surface 127 seated
on the frame 110. The seat surface 127 may be a rear surface of the
cylinder flange 125 that extends from the cylinder body 121 in a
radial direction.
[0086] The frame 110 may include a frame body 111 that surrounds
the cylinder body 121, and a cover coupling portion 115 that
extends in a radial direction of the frame body and is coupled to
the discharge cover 160.
[0087] The cover coupling portion 115 may have a plurality of cover
coupling holes 116, in which the coupling member coupled to the
discharge cover 160 may be inserted, and a plurality of the
cylinder coupling holes 118, in which the coupling member coupled
to the cylinder flange 125 may be inserted. The plurality of
cylinder coupling holes 118 may be defined at positions recessed
somewhat from the cover coupling portion 115.
[0088] The frame 110 may have a recess 117 recessed backward from
the cover coupling portion 115 to allow the cylinder flange 125 to
be inserted therein. That is, the recess 117 may be disposed to
surround the outer circumferential surface of the cylinder flange
125. The recess 117 may have a recessed depth corresponding to a
front to rear width of the cylinder flange 125.
[0089] A predetermined refrigerant flow space may be defined
between an inner circumferential surface of the recess 117 and the
outer circumferential surface of the cylinder flange 125. The
high-pressure gas refrigerant discharged from the discharge valve
161 may flow toward the outer circumferential surface of the
cylinder body 121 via the refrigerant flow space. The second filter
320 may be disposed in the refrigerant flow space to filter the
refrigerant.
[0090] In detail, a seat 113 having a stepped portion maybe
disposed on or at a rear end of the recess 117. The second filter
320 having a ring shape may be seated on the seat 113.
[0091] In a state in which the second filter 320 is seated on the
seat 113, when the cylinder 120 is coupled to the frame 110, the
cylinder flange 125 may push the second filter 320 from a front
side of the second filter 320. That is, the second filter 320 may
be disposed and fixed between the seat 113 of the frame 110 and the
seat surface 127 of the cylinder flange 125.
[0092] The second filter 320 may prevent foreign substances in the
high-pressure gas refrigerant discharged through the opened
discharge valve 161 from being introduced into the gas inflow 122
of the cylinder 120 and be configured to adsorb oil contained in
the refrigerant thereon. For example, the second filter 320 may
include a felt formed of polyethylene terephthalate (PET) fiber or
an adsorbent paper. The PET fiber may have superior heat-resistance
and mechanical strength. Also, a foreign substance having a size of
about 2 .mu.m or more, which is contained in the refrigerant, may
be blocked.
[0093] The high-pressure gas refrigerant passing through the flow
space defined between the inner circumferential surface of the
recess 117 and the outer circumferential surface of the cylinder
flange 125 may pass through the second filter 320. In this process,
the refrigerant may be filtered by the second filter 320.
[0094] FIG. 9 is a cross-sectional view illustrating a state in
which the cylinder and a piston are coupled to each other according
to an embodiment. FIG. 10 is a view of the cylinder according to an
embodiment. FIG. 11 is an enlarged cross-sectional view of portion
A of FIG. 9.
[0095] Referring to FIGS. 9 to 11, the cylinder 120 according to an
embodiment may include the cylinder body 121 having an
approximately cylindrical shape to form a first body end 121a and a
second body end 121b, and the cylinder flange 125 that extends from
the second body end 121b of the cylinder body 121 in a radial
direction. The first body end 121a and the second body end 121b
form both ends of the cylinder body 121 with respect to the central
portion 121c of the cylinder body 121 in an axial direction.
[0096] The cylinder body 121 may include a plurality of the gas
inflows 122, through which at least a portion of the high-pressure
gas refrigerant discharged through the discharge valve 161 may
flow. A third filter 330 may be disposed in the plurality of gas
inflows 122.
[0097] Each of the plurality of gas inflows 122 may be recessed
from the outer circumferential surface of the cylinder body 121 by
a predetermined depth and width. The refrigerant may be introduced
into the cylinder body 121 through the plurality of gas inflows 122
and the nozzle 123.
[0098] The introduced refrigerant may be disposed between the outer
circumferential surface of the piston 130 and the inner
circumferential surface of the cylinder 120 to serve as the gas
bearing with respect to movement of the piston 130. That is, the
outer circumferential surface of the piston 130 may be maintained
in a state in which the outer circumferential surface of the piston
130 is spaced apart from the inner circumferential surface of the
cylinder 120 by pressure of the refrigerant.
[0099] The plurality of gas inflows 122 may include first and
second gas inflows 122a and 122b disposed on a first side with
respect to the central portion 121c in an axial direction of the
cylinder body 121, and a third gas inflow 122c disposed on a second
side with respect to the central portion 121c in the axial
direction. The first and second gas inflows 122a and 122b may be
disposed at positions closer to the second body end 121b with
respect to the central portion 121c in the axial direction of the
cylinder body 121, and the third gas inflow 122c may be disposed at
a position closer to the first body end 121a with respect to the
central portion 121c in the axial direction of the cylinder body
121. That is, the plurality of gas inflows 122 may be provided in
numbers which are not symmetrical to each other with respect to the
central portion 121c in the axial direction of the cylinder body
121.
[0100] Referring to FIG. 10, the cylinder 120 may have a relatively
high inner pressure at a side of the second body end 121b, which
may be closer to a discharge-side of the compressed refrigerant
when compared to that of the first body end 121a, which may be
closer to a suction-side of the refrigerant. Thus, more gas inflows
122 may be provided at the side of the second body end 121b to
enhance a function of the gas bearing, and relatively less gas
inflows 122 may be provided at the side of the first body end
121a.
[0101] The cylinder body 121 may further include one or more nozzle
123 that extends from the plurality of gas inflows 122 toward the
inner circumferential surface of the cylinder body 121. Each nozzle
123 may have a width or size less than a width or size of the gas
inflow 122.
[0102] A plurality of the nozzles 123 may be provided along the gas
inflow 122, which may extend in a circular shape. The plurality of
nozzles 123 may be disposed to be spaced apart from each other.
[0103] The plurality of nozzles 123 may each include an inlet 123a
connected to the gas inflow 122, and an outlet 123b connected to
the inner circumferential surface of the cylinder body 121. Each
nozzle 123 may have a predetermined length from the inlet 123a
toward the outlet 123b.
[0104] A recessed depth and width of each of the plurality of gas
inflows 122 and a length of the nozzle 123 may be determined to
have adequate dimensions in consideration of a rigidity of the
cylinder 120, an amount of third filter 330, or a intensity in
pressure drop of the refrigerant passing through the nozzle 123.
For example, if the recessed depth and width of each of the
plurality of gas inflows 122 are too large, or the length of the
nozzle 123 is too short, rigidity of the cylinder 120 may be weak.
On the other hand, if the recessed depth and width of each of the
plurality of gas inflows 122 are too small, an amount of third
filter 330 provided in the gas inflow 122 may be too small. Also,
if the length of the nozzle 123 is too long, a pressure drop of the
refrigerant passing through the nozzle 123 may be too large, and it
may be difficult to perform the function as the gas bearing.
[0105] The inlet 123a of the nozzle 123 may have a diameter greater
than a diameter of the outlet 123b. In detail, if the diameter of
the nozzle 123 is too small, an amount of refrigerant, which may be
introduced from the nozzle 123, of the high-pressure gas
refrigerant discharged through the discharge valve 161 may be too
large, increasing flow loss in the compressor. On the other hand,
if the diameter of the nozzle 123 is too small, the pressure drop
in the nozzle 123 may increase, reducing a performance of the gas
bearing.
[0106] Thus, in this embodiment, the inlet 123a of the nozzle 123
may have a relatively large diameter to reduce the pressure drop of
the refrigerant introduced into the nozzle 123. In addition, the
outlet 123b may have a relatively small diameter to control an
inflow amount of gas bearing through the nozzle 123 to a
predetermined value or less.
[0107] The third filter 330 may prevent a foreign substance having
a predetermined size or more from being introduced into the
cylinder 120 and perform a function of adsorbing oil contained in
the refrigerant. The predetermined size may be about 1 .mu.m.
[0108] The third filter 330 may include a thread which is wound
around the gas inflow 122. In detail, the thread may be formed of a
polyethylene terephthalate (PET) material and have a predetermined
thickness or diameter.
[0109] The thickness or diameter of the thread may be determined to
have adequate dimensions in consideration of a rigidity of the
thread. If the thickness or diameter of the thread is too small,
the thread may be easily broken due to a very weak strength
thereof. On the other hand, if the thickness or diameter of the
thread is too large, a filtering effect with respect to foreign
substances may be deteriorated due to a very large pore in the gas
inflow 122 when the thread is wound.
[0110] For example, the thickness or diameter of the thread maybe
several hundreds .mu.m. The thread may be manufactured by coupling
a plurality of strands of a spun thread having several tens .mu.m
to each other, for example.
[0111] The thread may be wound several times, and an end of the
thread may be fixed with a knot, for example. A number of windings
of the thread may be adequately selected in consideration of the
pressure drop of the gas refrigerant and the filtering effect with
respect to foreign substances. If the number of thread windings is
too large, the pressure drop of the gas refrigerant may increase.
On the other hand, if the number of thread windings is too small,
the filtering effect with respect to foreign substances may be
reduced.
[0112] Also, a tension force of the wound thread may be adequately
controlled in consideration of deformation of the cylinder and
fixation of the thread. If the tension force is too large,
deformation of the cylinder 120 may occur. On the other hand, if
the tension force is too small, the thread may not be adequately
fixed to the gas inflow 122.
[0113] FIG. 12 is a cross-sectional view illustrating a refrigerant
flow in the linear compressor of FIG. 3. Referring to FIG. 12,
refrigerant flow in the linear compressor according to an
embodiment will be described hereinbelow.
[0114] Referring to FIG. 12, the refrigerant may be introduced into
the shell 101 through the suction inlet 104 and flow into the
suction muffler 150 through the suction guide 155. The refrigerant
may be introduced into the second muffler 153 via the first muffler
151 of the suction muffler 150 to flow into the piston 130. In this
way, suction noise of the refrigerant may be reduced.
[0115] A foreign substance having a predetermined size (about 25
.mu.m) or more, which is contained in the refrigerant, may be
filtered while passing through the first filter 310 provided on or
in the suction muffler 150. The refrigerant within the piston 130
after passing though the suction muffler 150 may be suctioned into
the compression space P through the suction hole 133 when the
suction valve 135 is opened.
[0116] When the refrigerant pressure in the compression space P is
above the predetermined discharge pressure, the discharge valve 161
may be opened. Thus, the refrigerant may be discharged into the
discharge space of the discharge cover 160 through the opened
discharge valve 161, flow into the discharge outlet 105 through the
loop pipe 165 coupled to the discharge cover 160, and be discharged
outside of the compressor 100.
[0117] At least a portion of the refrigerant within the discharge
space of the discharge cover 160 may flow toward the outer
circumferential surface of the cylinder body 121 via the space
defined between the cylinder 120 and the frame 110, that is, the
inner circumferential surface of the recess 117 of the frame 110
and the outer circumferential surface of the cylinder flange 125 of
the cylinder 120. The refrigerant may pass through the second
filter 320 disposed between the seat surface 127 of the cylinder
flange 125 and the seat 113 of the frame 110. In this way, a
foreign substance having a predetermined size (about 2 .mu.m) or
more may be filtered. Also, oil in the refrigerant may be adsorbed
onto or into the second filter 320.
[0118] The refrigerant passing through the second filter 320 may be
introduced into the plurality of gas inflows 122 defined in the
outer circumferential surface of the cylinder body 121. Also, while
the refrigerant passes through the third filter 330 provided on or
in the gas inflows 122, a foreign substances having a predetermined
size (about 1 .mu.m) or more, which is contained in the
refrigerant, may be filtered, and oil contained in the refrigerant
may be adsorbed.
[0119] The refrigerant passing through the third filter 330 may be
introduced into the cylinder 120 through the nozzle 123 and be
disposed between the inner circumferential surface of the cylinder
120 and the outer circumferential surface of the piston 130 to
space the piston 130 from the inner circumferential surface of the
cylinder 120 (gas bearing). As described above, the high-pressure
gas refrigerant may be bypassed within the cylinder 120 to serve as
the gas bearing with respect to the piston 130 which is
reciprocated, thereby reducing abrasion between the piston 130 and
the cylinder 120. Also, as oil is not used for the bearing,
friction loss due to oil may not occur even though the compressor
100 operates at a high rate.
[0120] Also, as the plurality of filters may be provided on the
path or passage of the refrigerant flowing in the compressor 100,
foreign substances contained in the refrigerant may be removed.
Thus, the refrigerant acting as the gas bearing may be improved in
reliability. Thus, it may prevent the piston 130 or the cylinder
120 from being worn by foreign substances contained in the
refrigerant. Also, as the oil contained in the refrigerant may be
removed by the plurality of filters, it may prevent friction loss
due to the oil from occurring.
[0121] The first, second, and third filters 310, 320, and 330 may
be referred to as a "filter device" in that the filters 310, 320,
and 330 filter the refrigerant that serves as the gas bearing. That
is, the filter device may include at least one filter member
disposed on or in the "refrigerant passage" from the suction inlet
104 to the nozzle 123 via the discharge valve 161. Thus, foreign
substances and oil in the refrigerant to be introduced into the
nozzle 123 may be filtered while passing through the filter
member.
[0122] Hereinafter, another embodiment will be described. This
embodiment may be the same as the previous embodiment except for an
arrangement of a second filter, and thus, different points
therebetween will be mainly described, and repetitive disclosure
has been omitted.
[0123] FIG. 13 is a cross-sectional view of illustrating a position
of a second filter is disposed according to another embodiment.
Referring to FIG. 13, linear compressor 100 according to this
embodiment may include a second filter 420 disposed between an
outer circumferential surface of cylinder flange 125 and an inner
circumferential surface of recess 117 of frame 110.
[0124] The second filter 420 may extend from a front end of the
cylinder flange part 125 in an axial direction of the compressor
100. Thus, at least a portion of a refrigerant discharged through
discharge valve 161 may flow backward along a longitudinal
direction of the second filter 420.
[0125] For example, the second filter 420 may include a felt formed
of polyethylene terephthalate (PET) fiber or an adsorbent paper.
The PET fiber may have superior heat-resistance and mechanical
strength. Also, a foreign substance having a size of about 2 .mu.m
or more, which may be contained in the refrigerant, may be
blocked.
[0126] As the second filter 420 may be disposed in a refrigerant
flow space defined between the cylinder 120 and the frame 110,
foreign substances in the refrigerant may be filtered, and oil
contained in the refrigerant may be adsorbed onto or into the
second filter 420.
[0127] According to embodiments disclosed herein, a compressor
including inner components may decrease in size to reduce a volume
of a machine room of a refrigerator and increase an inner storage
space of the refrigerant. Also, a drive frequency of the compressor
may increase to prevent performance of inner components from being
deteriorated due to the decreasing size thereof. In addition, as
the gas bearing may be applied between the cylinder and the piston,
friction force occurring due to oil may be reduced.
[0128] Further, as the plurality of filter devices may be provided
in the compressor, foreign substances or oil contained in the
compressed gas (or discharge gas) introduced to the outside of the
piston may be prevented from being introduced into the nozzle of
the cylinder. More particularly, the first filter may be provided
on the suction muffler to prevent the foreign substances contained
in the refrigerant from being introduced into the compression
chamber. Also, the second filter may be provided on the coupling
between the cylinder and the frame to prevent the foreign
substances and oil contained in the compressed refrigerant gas from
flowing into the gas inflow of the cylinder.
[0129] Also, the third filter may be provided on the gas inflow of
the cylinder to prevent the foreign substances and oil from being
introduced into the nozzle of the cylinder from the gas inflow.
Additionally, the filter device may be provided in the dryer
provided in the refrigerator to filter the moisture, foreign
substances, or oil contained in the refrigerant.
[0130] As described above, as foreign substances or oil contained
in the compression gas that acts as a bearing may be filtered
through the plurality of filtering devices provided in the
compressor and dryer, it may prevent the nozzle of the cylinder
from being blocked by the foreign substances or oil. As the
blocking of the nozzle of the cylinder is prevented, a gas bearing
effect may be effectively performed between the cylinder and the
piston, and thus, abrasion of the cylinder and the piston may be
prevented.
[0131] Embodiments disclosed herein provide a linear compressor in
which a gas bearing may easily operate between a cylinder and a
piston, and a refrigerant including a linear compressor.
[0132] Embodiments disclosed herein provide a linear compressor
that may include a shell including a suction inlet; a cylinder
provided in the shell to define a compression space for a
refrigerant; a piston reciprocated in an axial direction within the
cylinder; a discharge valve provided on or at one side of the
cylinder to selectively discharge the refrigerant compressed in the
compression space; a nozzle part or nozzle disposed in the cylinder
to introduce at least a portion of the refrigerant discharged
through the discharge valve into the cylinder; and a filter device
or filter provided in the shell. The filter device may include at
least one filter member disposed on or in a refrigerant passage
defined from the suction inlet to the nozzle part via the discharge
valve. Foreign substances or oil contained in the refrigerant to be
introduced into the nozzle part may be filtered while passing
through the at least one filter member.
[0133] The linear compressor may further include a suction muffler
provided in the shell to reduce noise of the refrigerant suctioned
through the suction inlet. The filter device may include a first
filter provided on the suction muffler. The suction muffler may
include a first muffler and a second muffler, and the first filter
may be disposed at a coupled portion between the first and second
mufflers.
[0134] The linear compressor may further include a groove part or
groove defined in one of the first muffler or the second muffler,
and a protrusion disposed on the other one of the first muffler or
the second muffler. The protrusion may be coupled to the groove
part. Both sides of the first filter may be disposed between the
groove part and the protrusion.
[0135] The first filter may include a magnetic material. The first
filter may be formed of a stainless steel material.
[0136] The linear compressor may further include a frame fixed to
an outside of the cylinder. The filter device may include a second
filter disposed in a refrigerant flow space between the cylinder
and the frame.
[0137] The cylinder may include a cylinder body, and a cylinder
flange part or flange that extends in a radial direction of the
cylinder body. A recess part or recess, in which the cylinder
flange part may be inserted, and a seat part or seat, on which one
surface of the cylinder flange part may be seated, may be provided
on the frame.
[0138] The second filter may be placed on the seat part of the
frame. The second filter may be placed between an outer
circumferential surface of the cylinder flange part, and an inner
circumferential surface of the recess part. The second filter may
have a ring shape. Further, the second filter may include a felt
formed of polyethylene terephthalate (PET) fiber.
[0139] The linear compressor may further include a gas inflow part
or gas inflow recessed from an outer circumferential surface of the
cylinder to communicate with the nozzle part. The filter device may
include a third filter disposed on or in the gas inflow part. The
third filter may include a thread having a preset or predetermined
thickness or diameter. The thread may be formed of a polyethylene
terephthalate (PET) material. The thread may be wound several times
around the gas inflow part.
[0140] Embodiments disclosed herein further provide a refrigerator
that may include a linear compressor including a reciprocating
piston and a cylinder to accommodate the piston and having an outer
circumferential surface to introduce a refrigerant; a filter device
provided in the linear compressor to filter the refrigerant
introduced through the outer circumferential surface of the
cylinder; a condenser to condense the refrigerant compressed in the
linear compressor; and a dryer to remove foreign substances or oil
contained in the refrigerant condensed in the condenser. The dryer
may include an adsorbent to adsorb the oil contained in the
refrigerant. The adsorbent may include a molecular sieve having a
grain shape and a plurality of holes to adsorb the oil. The
adsorbent may include an oil adsorbent paper or felt.
[0141] The dryer may include a first dryer filter disposed within
an inlet-side of the dryer; a second dryer filter that supports the
first dryer filter, the second dryer filter including the
adsorbent; and a third dryer filter that supports the second dryer,
the third dryer filter being disposed within an outlet-side of the
dryer.
[0142] The filter device may include a first filter including a
suction muffler to reduce flow noise of the refrigerant suctioned
into the linear compressor. The filter device may include a second
filter disposed on one side of the cylinder to filter at least a
portion of the refrigerant discharged from the cylinder. The filter
device may include a third filter wound around the outer
circumferential surface of the cylinder.
[0143] 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. 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.
[0144] 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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