U.S. patent application number 15/305911 was filed with the patent office on 2017-02-16 for cryogenic refrigeration system.
The applicant listed for this patent is Sunam Co., LTD.. Invention is credited to Woo Suk CHUNG.
Application Number | 20170045273 15/305911 |
Document ID | / |
Family ID | 54600605 |
Filed Date | 2017-02-16 |
United States Patent
Application |
20170045273 |
Kind Code |
A1 |
CHUNG; Woo Suk |
February 16, 2017 |
CRYOGENIC REFRIGERATION SYSTEM
Abstract
Provided is a cryogenic refrigeration system. The cryogenic
refrigeration system includes a cryogenic refrigerator, and a heat
dissipation module configured to cool the cryogenic refrigerator.
Here, the heat dissipation module includes a condenser configured
to condense a refrigerant that cools the cryogenic refrigerator,
and a heat exchanger connected to the cryogenic refrigerator to
circulate the refrigerant between the cryogenic refrigerator and
the condenser, thereby cooling the cryogenic refrigerator.
Inventors: |
CHUNG; Woo Suk; (Yongin-si,
KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Sunam Co., LTD. |
Anseong-si |
|
KR |
|
|
Family ID: |
54600605 |
Appl. No.: |
15/305911 |
Filed: |
April 23, 2015 |
PCT Filed: |
April 23, 2015 |
PCT NO: |
PCT/KR2015/004044 |
371 Date: |
October 21, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F25B 2600/2501 20130101;
F25B 49/02 20130101; F25B 2700/21151 20130101; F25B 9/14 20130101;
F25B 2700/1933 20130101; F25B 2309/1428 20130101; F25B 25/00
20130101; F25B 2339/047 20130101 |
International
Class: |
F25B 9/14 20060101
F25B009/14; F25B 49/02 20060101 F25B049/02 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 25, 2014 |
KR |
10-2014-0050248 |
Apr 14, 2015 |
KR |
10-2015-0052640 |
Claims
1. A cryogenic refrigeration system comprising: a cryogenic
refrigerator; and a heat dissipation module configured to cool the
cryogenic refrigerator, wherein the heat dissipation module
comprises: a condenser spaced apart from the cryogenic refrigerator
to condense a refrigerant that cools the cryogenic refrigerator;
and a heat exchanger connected to the cryogenic refrigerator to
circulate the refrigerant between the cryogenic refrigerator and
the condenser, thereby cooling the cryogenic refrigerator.
2. The cryogenic refrigeration system of claim 1, wherein the
cryogenic refrigerator comprises a gas cooling part configured to
expand a gas, thereby cooling the gas, and the heat exchanger
comprises a first heat exchanger configured to cool the gas cooling
part.
3. The cryogenic refrigeration system of claim 2, wherein the gas
cooling part comprises: a cylinder comprising an expansion region
in which the gas is expanded and a compression region defined below
the expansion region; a displacer disposed in the cylinder to move
between the expansion region and the compression region; and a
piston disposed below the displacer to move in the compression
region, wherein the first heat exchanger is disposed in the
compression region.
4. The cryogenic refrigeration system of claim 3, wherein the
cryogenic refrigerator further comprises a power generation part
configured to generate power provided to the displacer and the
piston, and the heat exchanger further comprises a second heat
exchanger configured to cool the power generation part.
5. The cryogenic refrigeration system of claim 4, wherein the
cryogenic refrigerator further comprises a power conversion part
disposed below the cylinder to convert the power generated in the
power generation part, and the heat exchanger further comprises a
third heat exchanger configured to cool the power conversion
part.
6. The cryogenic refrigeration system of claim 5, wherein the heat
dissipation module further comprises: a heat exchange collecting
line configured to connect the first heat exchanger to the second
heat exchanger; and a heat exchange supply line configured to
connect the first heat exchanger to the third heat exchanger.
7. The cryogenic refrigeration system of claim 5, wherein the heat
dissipation module comprises: a refrigerant collecting line
connected between the second heat exchanger and the condenser to
collect the refrigerant; and a refrigerant supply line connected
between the third heat exchanger and the condenser to supply the
refrigerant.
8. The cryogenic refrigeration system of claim 7, further
comprising: a compressor disposed in the refrigerant collecting
line to compress the refrigerant; and an expander disposed in the
refrigerant supply line to expand the refrigerant.
9. The cryogenic refrigeration system of claim 8, wherein the heat
dissipation module further comprises: a first pressure transducer
disposed in the refrigerant collecting line between the condenser
and the second heat exchanger to detect a pressure of the
refrigerant; a first temperature sensor disposed in the refrigerant
collecting line disposed adjacent to the first pressure transducer
to detect a temperature of the refrigerant; and a circulation flow
rate controller configured to receive a pressure detection signal
and a temperature detection signal of the first pressure transducer
and the first temperature sensor to control the expander.
10. The cryogenic refrigeration system of claim 8, wherein the heat
dissipation module further comprises: a bypass valve disposed in
the refrigerant collecting line between the condenser and the
compressor, and a bypass line branched from the bypass valve and
connected to the refrigerant supply line between the expander and
the third heat exchanger by bypassing the condenser.
11. The cryogenic refrigeration system of claim 10, wherein the
heat dissipation module further comprises: a second pressure
transducer disposed in the refrigerant collecting line between the
compressor and the second heat exchanger to detect a pressure of
the refrigerant; a second temperature sensor disposed in the
refrigerant collecting line disposed adjacent to the second
pressure transducer to detect a temperature of the refrigerant; and
a bypass controller configured to receive a pressure detection
signal and a temperature detection signal of the second pressure
transducer and the second temperature sensor to control the bypass
valve.
12. The cryogenic refrigeration system of claim 10, wherein the
heat dissipation module further comprises a sensitive heat tube
disposed in the refrigerant collecting line between the compressor
and the second heat exchanger to detect a temperature of the
refrigerant, thereby outputting turn-on and turn-off signals of the
expander.
13. A cryogenic refrigeration system comprising: a cryogenic
refrigerator comprising a power generation part, a power conversion
part configured to convert power generated in the power generation
part, and a gas cooling part configured to cool a gas by using the
power converted in the power conversion part; and a heat
dissipation module configured to circulate a refrigerant that cools
the cryogenic refrigerator into the power generation part, the
power conversion part, and the gas cooling part.
14. The cryogenic refrigeration system of claim 13, wherein the
heat dissipation module comprises: a condenser configured to
condense the refrigerant; and a heat exchanger configured to
provide the refrigerant condensed in the condenser to the power
generation part, the power conversion part, and the gas cooling
part.
15. The cryogenic refrigeration system of claim 14, wherein the
heat dissipation module further comprises: a refrigerant collecting
line configured to collect the refrigerant between the condenser
and the heat exchanger; and a refrigerant supply line configured to
supply the refrigerant between the condenser and the heat
exchanger.
16. The cryogenic refrigeration system of claim 15, wherein the
heat exchanger comprises: a first heat exchanger configured to cool
the gas cooling part; a second heat exchanger configured to cool
the power generation part; and a first heat exchanger configured to
cool the power conversion part.
17. The cryogenic refrigeration system of claim 16, wherein the
heat dissipation module further comprises: a heat exchange
refrigerant collecting line configured to collect the refrigerant
between the first heat exchanger and the second heat exchanger; and
a heat exchange refrigerant supply line configured to supply the
refrigerant between the first heat exchanger and the third heat
exchanger.
18. The cryogenic refrigeration system of claim 16, wherein the gas
cooling part comprises a cylinder having an expansion region in
which the gas is expanded and a compression region in which the gas
is compressed, and the first heat exchanger is disposed in the
compression region.
19. The cryogenic refrigeration system of claim 15, wherein the
heat dissipation module further comprises: a compressor disposed in
the refrigerant collecting line to compress the refrigerant; a
pressure transducer disposed between the compressor and the heat
exchanger to detect a pressure of the refrigerant; an expander
disposed in the refrigerant supply line to expand the refrigerant;
and a circulation flow rate controller configured to receive a
pressure detection signal of the pressure transducer to control the
expander.
20. The cryogenic refrigeration system of claim 15, wherein the
heat dissipation module further comprises: a bypass valve disposed
in the refrigerant collecting line; and a bypass line connected to
the bypass valve and connected to the refrigerant supply line by
bypassing the condenser.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This U.S. non-provisional patent application claims priority
under 35 U.S.C. .sctn.119 of Korean Patent Application No.
PCT/KR2015/004044, filed Apr. 23, 2015, the entire contents of
which are hereby incorporated by reference.
TECHNICAL FIELD
[0002] The present invention disclosed herein relates to a
cryogenic refrigeration system, and more particularly, to a
cryogenic refrigeration system capable of improving a coefficient
of performance thereof.
BACKGROUND ART
[0003] In general, a cryogenic refrigerator may be used to cool a
superconductor or a small-sized electronic component. For example,
the cryogenic refrigerator may include a stifling refrigerator, a
GM refrigerator, and a Joule-Thomson refrigerator. The
above-described cryogenic refrigerator may generate refrigeration
output through an expansion process of working fluid such as helium
or hydrogen. The expansion process may accompany heat generation of
a compression process. Accordingly, the cryogenic refrigerator may
be cooled by a heat dissipater. The typical cryogenic refrigerator
may be cooled by a dual heat dissipater. The dual heat dissipater
may include a water-cooling type heat dissipater and a vapor
compression refrigerator. The water-cooling type radiator may cool
the cryogenic refrigerator. The water-cooling type heat dissipater
may be cooled by the vapor compression refrigerator However, since
the water-cooling type heat dissipater uses water that has a low
cooling efficiency of performance, a coefficient of performance of
the cryogenic refrigerator may be reduced. In addition, the
water-cooling type heat dissipater and the vapor compression
refrigerator may increase costs for operating the cryogenic
refrigerator to reduce productivity.
DISCLOSURE OF THE INVENTION
Technical Problem
[0004] The present invention provides a cryogenic refrigeration
system capable of increasing a radiant efficiency due to a
coefficient of performance of refrigerant.
[0005] The present invention also provides a cryogenic
refrigeration system capable of minimizing costs for operating a
cryogenic refrigerator.
Technical Solution
[0006] Embodiments of the present invention provide a cryogenic
refrigeration system including: a cryogenic refrigerator; and a
heat dissipation module configured to cool the cryogenic
refrigerator. Here, the heat dissipation module includes: a
condenser spaced apart from the cryogenic refrigerator to condense
a refrigerant that cools the cryogenic refrigerator; and a heat
exchanger connected to the cryogenic refrigerator to circulate the
refrigerant between the cryogenic refrigerator and the condenser,
thereby cooling the cryogenic refrigerator.
[0007] In other embodiments of the present invention, cryogenic
refrigeration systems include: a cryogenic refrigerator comprising
a power generation part, a power conversion part configured to
convert power generated in the power generation part, and a gas
cooling part configured to cool a gas by using the power converted
in the power conversion part; and a heat dissipation module
configured to circulate a refrigerant that cools the cryogenic
refrigerator into the power generation part, the power conversion
part, and the gas cooling part.
Advantageous Effects
[0008] As described above, the cryogenic refrigeration system
according to the embodiments of the present invention may use
refrigerant having a coefficient of performance and/or a heat
absorption efficiency greater than that of the water to increase a
radiant efficiency of the cryogenic refrigerator. The cryogenic
refrigerator may be directly cooled by the heat dissipation module
to minimize the operational costs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a diagram illustrating an example of a cryogenic
refrigeration system according to the present invention.
[0010] FIG. 2 is a diagram illustrating a cryogenic refrigerator in
FIG. 1.
[0011] FIG. 3 is a diagram illustrating another example of the
cryogenic refrigeration system in FIG. 1.
[0012] FIG. 4 is a diagram illustrating still another example of
the cryogenic refrigeration system in FIG. 1.
BEST MODE FOR CARRYING OUT THE INVENTION
[0013] Exemplary embodiments of the present invention will be
described in detail with reference to the accompanying drawings.
Advantages and features of the present invention, and
implementation methods thereof will be clarified through following
embodiments described with reference to the accompanying drawings.
The present invention may, however, be embodied in different forms
and should not be construed as limited to the embodiments set forth
herein. Rather, these embodiments are provided so that this
invention will be thorough and complete, and will fully convey the
scope of the present invention to those skilled in the art.
Further, the present invention is only defined by scopes of claims.
Like reference numerals refer to like elements throughout.
[0014] In the specification, the technical terms are used only for
explaining a specific exemplary embodiment while not limiting the
present invention. In the specification, the terms of a singular
form may include plural forms unless referred to the contrary. The
meaning of `comprises` and/or `comprising` specifies a component, a
step, an operation and/or an element does not exclude other
components, steps, operations and/or elements. Also, it will be
understood that the terms such as chambers, units, arms, links,
blades, motors, pulleys, rotational shafts, and belts are used as
general mechanical terms in the specification. Since preferred
embodiments are provided below, the order of the reference numerals
given in the description is not limited thereto.
[0015] FIG. 1 is a diagram illustrating an example of a cryogenic
refrigeration system 10 according to the present invention. FIG. 2
is a diagram illustrating a cryogenic refrigerator 100 in FIG.
1.
[0016] Referring to FIGS. 1 and 2, the cryogenic refrigeration
system 10 according to the present invention may include the
cryogenic refrigerator 100 and a heat dissipation module 200. The
cryogenic refrigerator 100 may be cooled to a cryogenic
temperature. The heat dissipation module 200 may dissipate heat
from the cryogenic refrigerator 100.
[0017] The cryogenic refrigerator 100 may include a sterling
cryogenic refrigerator. According to an embodiment, the cryogenic
refrigerator 100 may include a power generation part 110, a power
conversion part 120, and a gas cooling part 130.
[0018] The power generation part 110 may generate rotational power
by external power. For example, the power generation part 110 may
include a motor. The power generation part 110 may be connected to
the power conversion part 120. The power generation part 110 may be
heated to a temperature greater than a room temperature. The power
generation part 110 may be heated to a temperature equal to or
greater than about 30.degree. C.
[0019] The power conversion part 120 may convert the rotational
power to reciprocating linear power. The power conversion part 120
may include a shaft 1 cam 125, a plurality of connecting rods 126,
and a housing 128. The shaft 122 may be connected to the power
generation part 110. The cam 124 may be connected between the shaft
122 and the connecting rods 126. The connecting rods 126 may extend
to the gas cooling part 130. The housing 128 may surround the cam
124. The housing 128 may be connected to the gas cooling part
130.
[0020] The housing 121 may be provided in the housing 128. Oil 121
may be heated by operation of the shaft 122, the cam 124, and the
connecting rods 126.
[0021] The gas cooling part 130 may be disposed on the power
conversion part 120. The gas cooling part 130 may cool gas 131 at
the cryogenic temperature. The gas 131 may include helium gas.
According to an example, the gas cooling part 130 may include a
cylinder 132, a displacer 140, and a piston 150. The cylinder 132
may be connected onto the power conversion part 120. The gas 131
may be provided into the cylinder 132. The displacer 140 and the
piston 150 may be connected to the connecting rods 126 to move up
and down in the cylinder 132. The displacer 140 may be disposed
above the pistol 150. One of the connecting rods 126 may pass
through the piston 150.
[0022] The cylinder 132 may include a gas expansion region 134, a
gas compression region 136, and a piston movement region 138. The
gas expansion region 134 may be disposed above the gas compression
region 136. The displacer 140 may be connected to one of the
connecting rods 126 to move up and down in the gas expansion region
134 and the gas compression region 136. The displacer 140 may
expand and cool the gas 131 in the gas expansion region 134.
Accordingly, the gas expansion region 134 may be a cooling region.
The gas compression region 136 may be connected to the rest of the
connecting rods 126 and disposed between the gas expansion region
134 and the piston movement region 138. The piston 150 may move up
and down in the piston movement region 138. Alternatively, the
piston movement region 138 may be a region through which one of the
connecting rods 126 passes. The displacer 140 and the piston 150
may compress the gas 131 in the gas compression region 136. The
compressed gas 131 may heat the cylinder 132 in the gas compression
region 136. Thus, the gas compression region 136 may be a heating
region.
[0023] The heat dissipation module 200 may circulate to supply
refrigerant to the power generation part 110, the power conversion
part 120, and the gas cooling part 130 to directly cool the
cryogenic refrigerator 100. The direct cooling method may have a
size smaller than that of the typical dual heat dissipater and
reduce maintenance costs. Accordingly, the cryogenic refrigeration
system 10 according to the present invention may reduce the
operational costs.
[0024] According to an example, the heat dissipation module 200 may
include a condenser 210, a compressor 220, heat exchangers 230, a
refrigerant expander 240, a refrigerant supply line 250, and a
refrigerant collecting line 260. The condenser 210 may condense the
refrigerant. The compressor 220 may be connected to the condenser
210. The condenser 220 may compress the refrigerant. According to
an example, the refrigerant may include R22, R123, R134a, HFC-407C,
HFC-407A, or R-123yf. The refrigerant may have a freezing point and
an evaporation point, which are lower than those of water. For
example, when water at a temperature of about 15.degree. C. is
heat-exchanged to about 30.degree. C. with respect to the cryogenic
refrigerator 100 at a temperature of about 63K, the water may have
a coefficient of performance (COP) of about 0.2625. Meanwhile, the
refrigerant of the R22 may have the coefficient of performance
greater than that of the water. When the R22 at a temperature of
about -30.degree. C. is heat-exchanged to about -15.degree. C., the
R22 may have the coefficient of performance of about 0.323. The
heat exchangers 230 may be connected to the power generation part
110, the power conversion part 120, and the gas cooling part 130.
The refrigerant supply line 250 may be connected between the
condenser 210 and the heat exchangers 230. A radiant efficiency of
the cryogenic refrigerator 100 may be increased. The refrigerant
expander 240 may be connected to the refrigerant supply line 250.
The refrigerant collecting line 260 may be connected between the
compressor 220 and the heat exchangers 230.
[0025] The condenser 210 may liquefy the refrigerant. The condenser
210 may include a water-cooling type condenser and an air-cooling
type condenser.
[0026] The refrigerant expander 240 may be disposed between the
condenser 210 and the heat exchangers 230. The refrigerant expander
240 may vaporize and cool the refrigerant. The cooled refrigerant
may be supplied to the heat exchangers 230 through the refrigerant
supply line 250, The refrigerant may be heated in the heat
exchangers 230.
[0027] The compressor 220 may supply the heated refrigerant to the
condenser 210 with a predetermined pressure. The refrigerant in a
gas state may be supplied to the condenser 210. The refrigerant may
be circulated between the heat exchangers 230 and the condenser
210.
[0028] The heat exchangers 230 may cool the power generation part
110, the power conversion part 120, and the gas cooling part 130.
According to an example, the heat exchangers 230 may include a gas
heat exchanger 232, an oil heat exchanger 234, and a motor heat
exchanger 236.
[0029] The gas heat exchanger 232 may be disposed in the
compression region 136. The gas heat exchanger 232 may cool the
cylinder 132 in the compression region 136. The heat exchange
supply line 233 may connect the gas heat exchanger 232 to the oil
heat exchanger 234. The heat exchange collecting line 235 may
connect the gas heat exchanger 232 to the motor heat exchanger 236.
The refrigerant may be sequentially supplied to the oil heat
exchanger 234, the gas heat exchanger 232, and the motor heat
exchanger 236. A first protection cover 312 may be disposed to
surround the gas heat exchanger 232. The first protection cover 312
may protect the gas heat exchanger 232. On the other hand, the
first protection cover 312 may prevent dew formation caused by
cooling of the gas heat exchanger 231.
[0030] The power generation part 234 may be disposed on the power
conversion part 120. The oil heat exchanger 234 may cool the oil in
the power conversion part 120. The oil heat exchanger 234 may be
connected to the refrigerant supply tine 250. A second protection
cover 314 may be disposed to surround the heat exchanger 234. The
second protection cover 314 may protect the oil heat exchanger
234.
[0031] The motor heat exchanger 236 may be disposed on the power
generation part 110. The motor heat exchanger 236 may cool the
power generation part 110. The motor heat exchanger 236 may be
connected to the refrigerant collecting line 260.
MODE FOR CARRYING OUT THE INVENTION
[0032] FIG. 3 is a diagram illustrating another example of the
cryogenic refrigeration system 10 in FIG. 1.
[0033] Referring to FIG. 3, the heat dissipation module 200 may
include a first pressure transducer 272, a first temperature sensor
274, and a circulation flow rate controller 276.
[0034] The first pressure transducer 272 may be disposed in the
refrigerant collecting line 260 between the heat exchangers 230 and
the compressor 220. The first pressure transducer 272 may detect a
pressure of the refrigerant.
[0035] The first temperature sensor 274 may be disposed in the
refrigerant collecting line 260 disposed adjacent to the first
pressure transducer 272. The first temperature sensor 274 may
detect a temperature of the refrigerant.
[0036] The circulation flow rate controller 276 may be connected to
the first pressure transducer 272, the first temperature sensor
274, and the refrigerant expander 240. Also, the circulation flow
rate controller 276 may receive a detection signal of the
temperature and the pressure of the first pressure transducer 272
and the first temperature sensor 274. The circulation flow rate of
the refrigerant may be controlled on the basis of the temperature
and the pressure. The refrigerant expander 240 may control the
circulation flow rate of the refrigerant according to the control
signal of the circulation flow rate controller 276.
[0037] The cryogenic refrigerator 100 and the condenser 210, the
compressor 220, the heat exchangers 230, the refrigerant expander
240, the refrigerant supply line 250, and the refrigerant
collecting line 260 of the heat dissipation module 200 may be the
same as those in FIGS. 1 and 2.
[0038] FIG. 4 is a diagram illustrating still another example of
the cryogenic refrigeration system 10 in FIG. 1.
[0039] Referring to FIG. 4, the heat dissipation module 200 may
include a second temper sensor 282, a second pressure transducer
284, a bypass valve 286, a bypass controller 288, a bypass line
290, and a sensitive heat tube 292.
[0040] The second temperature sensor 282 may be disposed in the
refrigerant collecting line 260. The second temperature sensor 282
may detect the temperature of the refrigerant.
[0041] The second pressure transducer 284 may be disposed in the
refrigerant collecting line 260. The second pressure transducer 284
may detect the pressure of the refrigerant.
[0042] The bypass valve 286 may be disposed in the refrigerant
collecting line 260 between the condenser 210 and the compressor
220. The bypass valve 286 may be connected to the bypass line 290.
The bypass valve 286 may include a three-way valve.
[0043] The bypass controller 288 may control the bypass valve 286.
The bypass controller 288 may receive temperature and pressure
signals of the second temperature sensor 282 and the second
pressure transducer 284.
[0044] The bypass line 290 may detour the condenser 210 to connect
the refrigerant collecting line 260 to the refrigerant supply line
250. According to an example, the bypass line 290 may be branched
from the bypass valve 286. The bypass line 290 may be connected to
the refrigerant supply line 250 between the heat exchangers 230 and
the refrigerant expander 240. For example, when the temperature of
the refrigerant of the refrigerant collecting line 260 is low, the
bypass controller 288 may allow the refrigerant to detour from the
refrigerant collecting line 260 to the refrigerant supply line 250
through the bypass line 290. Also, when the pressure of the
refrigerant of the refrigerant collecting line 260 is high, the
bypass controller 288 may allow the refrigerant to detour from the
refrigerant collecting line 260 to the refrigerant supply line
250
[0045] The sensitive heat tube 292 may be disposed in the
refrigerant collecting line 260, The sensitive heat tube 292 may be
connected to the refrigerant expander 240. The sensitive heat tube
292 may detect the temperature of the refrigerant in the
refrigerant collecting line 260. The sensitive heat tube 292
regulates the refrigerant expander 240 on the basis of the
temperature of the refrigerant. The sensitive heat tube 292 may
output a turn-on signal and a turn-off signal of the refrigerant
expander 240. When the temperature of the refrigerant is high, the
sensitive heat tube 292 may output the turn-on signal. When the
temperature of the refrigerant is low, the sensitive heat tube 292
may output the turn-off signal.
[0046] The cryogenic refrigerator 100 and the condenser 210, the
compressor 220, the heat exchangers 230, the refrigerant expander
240, the refrigerant supply line 250, and the refrigerant
collecting line 260 of the heat dissipation module 200 may be the
same as those in FIGS. 1 and 2.
[0047] Although the exemplary embodiments of the present invention
have been described, it is understood that the present invention
should not be limited to these exemplary embodiments but various
changes and modifications can be made by one ordinary skilled in
the art within the spirit and scope of the present invention as
hereinafter claimed. Thus, the above-disclosed embodiments are to
be considered illustrative and not restrictive.
INDUSTRIAL APPLICABILITY
[0048] According to the embodiment of the present invention, the
cryogenic refrigerator may increase the radiant efficiency thereof
to minimize the operational costs. In addition, the cryogenic
refrigerator may effectively cool the low temperature
superconductor or high temperature superconductor. The
superconductor may be used as a source material for a power plant,
a substation, a magnetic resonance device, a magnetic levitation
train, a superconductor research center. The cryogenic refrigerator
may be widely used in the field of superconductor technology.
Furthermore, the cryogenic refrigerator may be mounted on a tensile
tester for cryogenic metal.
* * * * *