CN2874363Y - Stirling refrigerating system driven by oil lubrication compressor - Google Patents

Stirling refrigerating system driven by oil lubrication compressor Download PDF

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Publication number
CN2874363Y
CN2874363Y CN 200520018268 CN200520018268U CN2874363Y CN 2874363 Y CN2874363 Y CN 2874363Y CN 200520018268 CN200520018268 CN 200520018268 CN 200520018268 U CN200520018268 U CN 200520018268U CN 2874363 Y CN2874363 Y CN 2874363Y
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China
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compressor
oil
refrigerating system
piston
cylinder
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Expired - Fee Related
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CN 200520018268
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Chinese (zh)
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罗二仓
吴张华
戴巍
吴剑峰
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Technical Institute of Physics and Chemistry of CAS
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Technical Institute of Physics and Chemistry of CAS
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Priority to CN 200520018268 priority Critical patent/CN2874363Y/en
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Abstract

The utility model relates to an adopt stirling refrigerating system of oil lubrication compressor drive, including a compressor, its motor links to each other with compression piston and exhaust piston respectively through the crank link mechanism, link to each other in proper order between compression piston and exhaust piston has room temperature end cooler, regenerator, and cold junction heat exchanger, still include an oil lubrication mechanism in the compressor, this oil lubrication mechanism is a loop that has the oil pump, can spray the lubricating oil of compressor cavity bottom into the cylinder-piston clearance of compression piston and exhaust piston, lubricate; the front parts of the compression piston and the exhaust piston respectively comprise an elastic membrane; a thermal buffer cavity is connected between the cold-end heat exchanger and the exhaust piston, and one end of the thermal buffer cavity close to the exhaust piston is also connected with a room-temperature heat exchanger. The utility model discloses a refrigeration system that obtains to the improvement of traditional stirling refrigeration technology is when keeping high efficiency, environmental protection advantage, and its life-span also obtains increasing substantially to the processing cost obtains greatly reduced.

Description

A kind of Stirling refrigerating system that adopts oil lubricating compressor to drive
Technical field
The utility model belongs to refrigeration and cryogenic technique field, specifically relates to a kind of Stirling refrigerating system that adopts oil lubricating compressor to drive.
Background technology
As everyone knows, the Stirling system is the thermal machine of a kind of thermal efficiency height, environmental protection (employing inert gas), and still, sterlin refrigerator in the past generally can not adopt the driven compressor of oil lubrication, caused its reliability relatively poor, general service life is only at thousands of hours; In addition, for dry friction that reduces to bring because of oil-free lubrication and then the problem that reduces mechanical efficiency, its cylinder, piston need adopt the processing of special material, precision etc. usually, cause its cost of manufacture very high thus.Therefore, although traditional stirling refrigeration has environmental protection (because of inert gases such as employing helium) and the high advantage of efficient, it fails to obtain large-scale commercial the application always.Recently, though the Stirling refrigerating system that the linear compressor of employing flat spring support drives occurred, but, therefore, yet do not obtain business-like application at present because this linear compressor requires high process technology, mounting technology and special cylinder-piston material.The difficult point of above-mentioned technology remains because compressor can not adopt due to the oil lubrication.
At present, the monoblock type sterlin refrigerator system of typical case's employing oil-free lubrication as shown in Figure 1, it mainly comprises: the compressor 1 of (1) oil-free lubrication, and it generally is crank-link type, is driven the compression piston 11 and the exhaust pition 12 of two angled motions by driven by motor; (2) the indoor temperature end cooler 2; (3) regenerator 3; (4) cool end heat exchanger 4.This Stirling refrigerating system generally all adopts gases such as helium as working medium, and its major defect is: in the refrigeration system lubricating oil can not be arranged.Otherwise, 1, lubricant pollution can make heat exchanger in the system and regenerator exchange capability of heat descend, and causes refrigeration performance to descend; 2, the lubricating oil obstruction may take place flow resistance is increased, cause performance to descend; 3 in addition because lubricating oil freezes etc. former thereby cisco unity malfunction.Therefore, the compressor of traditional Stirling refrigerating system can only adopt oil-free lubrication.Still do not have at present to propose to adopt oil lubricating compressor and can avoid lubricating oil to enter the embodiment of refrigeration system again.
The utility model content
If being exactly monoblock type sterlin refrigerator system for the oil-free lubrication that overcomes prior art, the purpose of this utility model used lubricating oil, can not avoid lubricating oil to enter refrigeration system, may system's refrigeration performance be descended owing to the pollution or the generation obstruction of lubricating oil, or because lubricating oil freezes etc. the defective of former thereby cisco unity malfunction, thereby provide a kind of compressor life-span to improve greatly, can reduce simultaneously the mechanical processing difficulty of compressor again, and high reliability, low-cost, high efficiency, the Stirling refrigerating system that the employing oil lubricating compressor of complete environmental protection drives.
The purpose of this utility model realizes by the following technical solutions:
The Stirling refrigerating system that the employing oil lubricating compressor that the utility model provides drives as shown in Figure 2, comprising: a compressor 1; One motor links to each other with exhaust pition 12 with the compression piston 11 of compressor 1 respectively by toggle, and promotes compression piston 11 and exhaust pition 12 moves in cylinder respectively; Be connected with indoor temperature end cooler 2, regenerator 3, cool end heat exchanger 4, heat buffering cavity 7 and room temperature heat exchanger 8 in the cylinder that compression piston 11 and exhaust pition are 12 successively, this refrigeration system also comprises:
Be installed in first elastic membrane 6 between the compression piston 11 and indoor temperature end cooler 2 in the cylinder, make the compression cylinder 14 that compression piston 11 can move betwixt with formation;
Be installed in second elastic membrane 61 between the room temperature heat exchanger 8 and exhaust pition 12 in the cylinder, make the exhaust cylinder 15 that compression piston 12 can move betwixt with formation; With
An oil lubrication mechanism 5, this oil lubrication mechanism 5 comprises: the lubricating oil that is contained in compressor cavity bottom; Be communicated with the connecting pipe of compressor cavity bottom and compression cylinder 14 and be installed in ducted first oil pump 9; With the connecting pipe that is communicated with compressor cavity bottom and exhaust cylinder 15 be installed in ducted second oil pump 91.
Described elastic membrane is the diaphragm that elastomeric organic material or metal material make, described organic material is fluorubber, latex, natural rubber etc., described metal material then is beryllium-bronze, elastic stainless steel material etc., and the size of their thickness and diameter is designed according to the volume flow in cross section, place and the fatigue limit of elastomeric material.Usually, the material thickness of elastic membrane is between 0.3~5mm, and its diameter is then according to the displacement allowable of its elastic membrane gas motion displacement greater than this section.
Described heat buffering cavity is the thin-walled empty pipe of low thermal conductivity materials such as stainless steel, titanium alloy or pottery, and its wall thickness is generally about 1~3 times of the critical pressure-bearing thickness of pipe, usually between 0.1mm~5mm.
Described first oil pump 9 and second oil pump 91 are gear pump.
The Stirling refrigerating system that the employing oil lubricating compressor that the utility model provides drives can be a multistage refrigerating system, can install n level regenerator additional as required between described regenerator 3 and cool end heat exchanger 4, and wherein n is the positive integer greater than 2.For example add secondary regenerator 10, or add secondary regenerator 10 and three grades of regenerators 13 successively.
Key technology of the present utility model is to have used a kind of highly elastic film, and the brief description of its principle is as follows:
The pressure of supposing the flexible sheet both sides is p 1And p 2, the quality of flexible sheet is m, and coefficient of elasticity is K, and the cross-sectional area of flexible sheet is A, then has:
(p 1-p 2)A=Kx+mx″ (1)
Wherein: x is the displacement of flexible sheet, x " for displacement is an acceleration to the second dervative of time.
With p1, p2, x with the simple harmonic quantity form
p 1=P 1·e jωt
p 2=P 2·e jωt
x=X·e jωt
x″=-ω 2·X·e jωt
P wherein 1, P 2, X is respectively the amplitude of each simple harmonic quantity, ω is an angular frequency, substitution (1) formula can further be write as following form:
(P 1-P 2)A=(K-mω 2)X (2)
As can be seen from the above equation, if the elasticity of elastic membrane is fine, mean that then the stiffness coefficient K of elastic membrane is tending towards 0; In addition, if the very light weight of diaphragm, then quality m also is tending towards 0, like this, just can draw the pressure P of diaphragm both sides under the situation of the limit 1, P 2Identical.In fact, compare, by the elasticity and the caused contribution of quality very little (two magnitudes are following) of diaphragm, so can think that the ability and the gas of diaphragm transmission sound wave are identical with the gas pressure of film both sides.Lubricating oil in can be in preventing compressor enters in the refrigeration system part simultaneously, again can be effectively the mechanical power of compressor be delivered to refrigeration system with the form of sound wave.
The Stirling refrigerating system that the employing oil lubricating compressor that the utility model provides drives, compared with prior art, except having used a kind of highly elastic film, also increased thermal buffer tube, thereby can make exhaust pition in room temperature environment work, can reduce refrigeration losses on the one hand, guarantee that on the other hand exhaust pition can be lubricated at room temperature environment.
The refrigerating system that the utility model obtains by the improvement to traditional stirling refrigeration technology is when keeping efficient, environmental protection advantage, and its life-span also is greatly improved, and processing cost is reduced greatly.
Description of drawings
Fig. 1 is the monoblock type sterlin refrigerator system schematic of traditional employing oil-free lubrication;
Fig. 2 is the single-stage Stirling refrigerating system schematic diagram that the employing oil lubricating compressor of embodiment 1 drives;
Fig. 3 is the secondary Stirling refrigerating system schematic diagram that the employing oil lubricating compressor of embodiment 2 drives;
Fig. 4 is three grades of Stirling refrigerating system schematic diagrames that the employing oil lubricating compressor of embodiment 3 drives;
Wherein: 1. compressor, 2. indoor temperature end cooler, 3. regenerator, 4. cool end heat exchanger, 5. oil lubrication mechanism, 6. first elastic membrane, 61. second elastic membrane, 7. heat buffering cavity, 8. room temperature heat exchanger, 9. first oil pump, 91. second oil pumps, 10. secondary regenerator, 11. compression piston, 12. exhaust pitions, 13. 3 grades of regenerators, 14. compression cylinder, 15. exhaust cylinders.
The specific embodiment
The Stirling refrigerating system that the employing oil lubricating compressor that the utility model provides drives as shown in Figure 2, comprising: a compressor 1; One motor links to each other with exhaust pition 12 with the compression piston 11 of compressor 1 respectively by toggle, and promotes compression piston 11 and exhaust pition 12 moves in cylinder respectively; Be connected with indoor temperature end cooler 2, regenerator 3, cool end heat exchanger 4, heat buffering cavity 7 and room temperature heat exchanger 8 in the cylinder that compression piston 11 and exhaust pition are 12 successively, this refrigeration system also comprises: be installed in first elastic membrane 6 between the compression piston 11 and indoor temperature end cooler 2 in the cylinder, make the compression cylinder 14 that compression piston 11 can move betwixt with formation; Be installed in second elastic membrane 61 between the room temperature heat exchanger 8 and exhaust pition 12 in the cylinder, make the exhaust cylinder 15 that compression piston 12 can move betwixt with formation; With an oil lubrication mechanism 5, this oil lubrication mechanism 5 comprises: the lubricating oil that is contained in compressor cavity bottom; Be communicated with the connecting pipe of compressor cavity bottom and compression cylinder 14 and be installed in ducted first oil pump 9; With the connecting pipe that is communicated with compressor cavity bottom and exhaust cylinder 15 be installed in ducted second oil pump 91.This refrigeration system can be a multistage refrigerating system.Describe the utility model in detail below in conjunction with specific embodiment.
The single-stage Stirling refrigerating system that the employing oil lubricating compressor that embodiment 1, the utility model provide drives
As shown in Figure 2, the single-stage Stirling refrigerating system that the employing oil lubricating compressor that the utility model provides drives comprises: the compressor assembly 1 of (1) oil lubrication, it is by toggle of motor drives, this toggle links to each other with exhaust pition 12 with compression piston 11 respectively, and the movement angle of the two differs 90 degree.In addition, the oil lubrication mechanism 5 of an employing gear pump 9 continuously delivers to the grease pump of compressor cavity bottom the piston-cylinder clearance of compression piston 11 and exhaust pition 12, makes it obtain good lubrication; Include the elastic membrane 6 of the fluorubber material made of the Viton trade mark that a du pont company produces in the place ahead of described compression piston 11 and exhaust pition 12, lubricating oil will can not enter refrigeration system inside, and two piston end surface accumulation, effect by gravity and gas turns back to compressor cavity bottom then, circulates again.(2) sound wave of compression piston reciprocating motion generation is transported to refrigeration system by the effect of elastic membrane with mechanical power (form of sound wave), by the inner hot junction of refrigeration system cooler---the synergy of indoor temperature end cooler 2, regenerator 3, cool end heat exchanger 4, heat buffering cavity 7 and will import refrigeration system, part sound merit produces refrigeration effect, and other a part of expansion work then obtains reclaiming in exhaust pition 12 by the elastic membrane feedback effect of exhaust pition front.Equally, because the effect of this elastic membrane, the lubricating oil in the exhaust pition between cylinder-piston will can not enter into refrigeration system.Heat buffering cavity 7 makes exhaust pition be operated in room temperature environment, helps the lubricated of lubricating oil.(3) this refrigeration system adopts helium to make working medium, and operating pressure is 10~30bar, and operating frequency is between 50~60Hz.The length of regenerator is between 10~30mm.The thickness of elastic membrane is between 0.3mm-5mm.This cooling flow is applicable to refrigerator, air-conditioning, heat pump operation temperature area.
The secondary Stirling refrigerating system that the employing oil lubricating compressor that embodiment 2, the utility model provide drives
As shown in Figure 3, the secondary Stirling refrigerating system that the employing oil lubricating compressor that the utility model provides drives comprises: the compressor assembly 1 of (1) oil lubrication, it is by toggle of motor drives, this toggle links to each other with exhaust pition 12 with compression piston 11 respectively, exists movement angle poor between the three.In addition, the oil lubrication mechanism 5 of an employing gear pump 9 continuously delivers to the grease pump of compressor cavity bottom the piston-cylinder clearance of compression piston 11 and exhaust pition 12, makes it obtain good lubrication; Include the elastic membrane 6 that a natural rubber material is made in the place ahead of described compression piston 11 and exhaust pition 12, lubricating oil will can not enter refrigeration system inside, and two piston end surface accumulation, effect by gravity and gas turns back to compressor cavity bottom then, circulates again.(2) every grade has an exhaust pition 12.The sound wave that the compression piston reciprocating motion produces is transported to refrigeration system by the effect of elastic membrane with mechanical power (form of sound wave), hot junction cooler---the synergy of indoor temperature end cooler 2, regenerator 3, secondary regenerator 10, heat buffering cavity 7 by the inner first order of refrigeration system, to import refrigeration system part sound merit and produce refrigeration effect, other a part of expansion work then obtains reclaiming in one-level exhaust pition and secondary exhaust pition by the elastic membrane feedback effect of one-level exhaust pition 12 and secondary exhaust pition 12 respectively.Equally, because the effect of this elastic membrane, the lubricating oil in the exhaust pition between cylinder-piston will can not enter into refrigeration system.Heat buffering cavity 7 makes exhaust pition be operated in room temperature environment, helps the lubricated of lubricating oil.(3) this refrigeration system adopts helium to make working medium, and operating pressure is 10~30bar, and operating frequency is between 50~60Hz.The length of single-stage regenerator is between 30~80mm.The thickness of elastic membrane is between 0.3mm-5mm.This cooling flow is used to obtain the low temperature of 4K-80K warm area.
Three grades of Stirling refrigerating systems that the employing oil lubricating compressor that embodiment 3, the utility model provide drives
As shown in Figure 4, three grades of Stirling refrigerating systems that the employing oil lubricating compressor that the utility model provides drives comprise: the compressor assembly 1 of (1) oil lubrication, it is by toggle of motor drives, this toggle links to each other with an exhaust pition 12 with compression piston 11 respectively, exists movement angle poor between the two.In addition, the oil lubrication mechanism 5 of an employing gear pump 9 continuously delivers to the grease pump of compressor cavity bottom the piston-cylinder clearance of compression piston 11 and exhaust pition 12, makes it obtain good lubrication; Include the elastic membrane 6 of a beryllium-bronze material made in the place ahead of described compression piston 11 and exhaust pition 12, lubricating oil will can not enter refrigeration system inside, and two piston end surface accumulation, effect by gravity and gas turns back to compressor cavity bottom then, circulates again.(2) sound wave of compression piston reciprocating motion generation is transported to refrigeration system by the effect of elastic membrane with mechanical power (form of sound wave), indoor temperature end cooler 2, regenerator 3 by the inner first order of refrigeration system, part sound merit produces refrigeration effect in the one-level regenerator, part expansion work is deflated piston 12 by elastic membrane and reclaims, the remaining secondary regenerator 10 that flows to.Equally in the secondary regenerator, part sound merit produces refrigeration, and a part of expansion work is deflated piston 12 by elastic membrane and reclaims, and remaining flows to three grades of regenerators, and part sound merit produces refrigeration, and a part of expansion work is deflated piston 12 by elastic membrane and reclaims.Equally, because the effect of this elastic membrane, the lubricating oil in the exhaust pition between cylinder-piston will can not enter into refrigeration system.(3) this refrigeration system adopts helium to make working medium, and operating pressure is 10~30bar, and operating frequency is between 50~60Hz.The length of every grade of regenerator is between 30~80mm.The thickness of elastic membrane is between 0.3mm-5mm.
Can form the more multistage monoblock type Stirling refrigerating system that respectively has exhaust pition in theory, but system complexity also rises three grades on generally not super ground thereupon.

Claims (8)

1, a kind of Stirling refrigerating system that adopts oil lubricating compressor to drive comprises:
A compressor (1);
One motor links to each other with exhaust pition (12) with the compression piston (11) of compressor (1) respectively by toggle, and promotes compression piston (11) and exhaust pition (12) moves in cylinder respectively; Be connected with indoor temperature end cooler (2), regenerator (3), cool end heat exchanger (4), heat buffering cavity (7) and room temperature heat exchanger (8) in the cylinder between compression piston (11) and exhaust pition (12) successively, it is characterized in that: also comprise:
Be installed in first elastic membrane (6) between the compression piston (11) and indoor temperature end cooler (2) in the cylinder, make the compression cylinder (14) that compression piston (11) is mobile betwixt with formation;
Be installed in second elastic membrane (61) between the room temperature heat exchanger (8) and exhaust pition (12) in the cylinder, make the exhaust cylinder (15) that compression piston (12) is mobile betwixt with formation; With
An oil lubrication mechanism (5), this oil lubrication mechanism (5) comprising: the lubricating oil that is contained in compressor cavity bottom; Be communicated with the connecting pipe of compressor cavity bottom and compression cylinder (14) and be installed in ducted first oil pump (9); With the connecting pipe that is communicated with compressor cavity bottom and exhaust cylinder (15) be installed in ducted second oil pump (91).
2, the Stirling refrigerating system of employing oil lubricating compressor driving as claimed in claim 1, it is characterized in that: described elastic membrane is the diaphragm that elastomeric organic material or metal material make.
3, the Stirling refrigerating system of employing oil lubricating compressor driving as claimed in claim 1, it is characterized in that: described elastic membrane is the diaphragm that fluorubber, latex or natural rubber make.
4, the Stirling refrigerating system of employing oil lubricating compressor driving as claimed in claim 1, it is characterized in that: described elastic membrane is the diaphragm that beryllium-bronze or stainless steel material make.
5, the Stirling refrigerating system of employing oil lubricating compressor driving as claimed in claim 1 is characterized in that: the thin-walled empty pipe that described heat buffering cavity (7) makes for low thermal conductivity material.
6, the Stirling refrigerating system of employing oil lubricating compressor driving as claimed in claim 5 is characterized in that: the thin-walled empty pipe that described heat buffering cavity (7) makes for stainless steel, titanium alloy or pottery.
7, the Stirling refrigerating system of employing oil lubricating compressor driving as claimed in claim 1, it is characterized in that: described oil pump is a gear pump.
8, the Stirling refrigerating system of employing oil lubricating compressor driving as claimed in claim 1, it is characterized in that: the Stirling refrigerating system that described employing oil lubricating compressor drives is a multistage refrigerating system, between described regenerator (3) and cool end heat exchanger (4) n level regenerator is housed, wherein n is the positive integer greater than 2.
CN 200520018268 2005-05-12 2005-05-12 Stirling refrigerating system driven by oil lubrication compressor Expired - Fee Related CN2874363Y (en)

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Application Number Priority Date Filing Date Title
CN 200520018268 CN2874363Y (en) 2005-05-12 2005-05-12 Stirling refrigerating system driven by oil lubrication compressor

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110966790A (en) * 2018-09-30 2020-04-07 中国科学院理化技术研究所 Thermally driven Stirling refrigerator

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110966790A (en) * 2018-09-30 2020-04-07 中国科学院理化技术研究所 Thermally driven Stirling refrigerator
CN110966790B (en) * 2018-09-30 2021-07-20 中国科学院理化技术研究所 Thermally driven Stirling refrigerator

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Granted publication date: 20070228

Termination date: 20100512