Low temperature refrigerator based on Stirling refrigerator

Abstract

The present invention discloses a low-temperature refrigerator based on a Stirling refrigerator. The traditional cascade vapor compression refrigeration system is inefficient and unreliable. A cooling pipe is arranged on the back of the refrigerator body corresponding to the position of the freezer compartment in the present invention, and the cooling pipe is a serpentine copper pipe with both ends closed. A Stirling refrigerator is arranged in the refrigeration working chamber, and the cold head of the Stirling refrigerator is arranged through the heat-insulating partition, and the cold head and the cooling pipe are connected by a flexible heat-conducting member. The flexible heat-conducting member is a flexible metal sheet or metal mesh bent into a U-shape or an S-shape, with an upper and a lower arm, and can produce elastic deformation in the longitudinal direction. The lower arm of the flexible heat-conducting member is welded to the cold head, and the upper arm is welded to one end of the cooling pipe. The present invention adopts a Stirling refrigerator, which has a good refrigeration effect, is energy-saving and environmentally friendly, and solves the problems of large vibration, high noise, and short life of the cold head of the Stirling refrigerator through the flexible heat-conducting member.

Description

Technical Field

[0001] The invention belongs to the technical field of refrigeration, and relates to a low-temperature refrigerator based on a Stirling refrigerator. Background Art

[0002] With the rapid development of the biological and medical industries, the demand for ultra-low temperature refrigerators for long-term storage of biological and medical samples, reagents and other biological materials is increasing. Such ultra-low temperature refrigerators generally require a storage temperature below -70°C and a stable refrigeration system to achieve long-term and reliable storage of biological materials. However, for a long time, my country's deep-freeze refrigerator industry has been in a blank stage, and foreign brands have always dominated the market.

[0003] The new cryogenic refrigerator has a relatively high refrigeration efficiency under large temperature difference refrigeration conditions (refrigeration temperature difference>60℃). Especially in the ultra-low temperature refrigerator refrigeration system below -70℃, the refrigeration efficiency of the new cryogenic refrigerator can reach more than twice that of the traditional cascade vapor compression refrigeration system, which has a significant energy-saving advantage. At the same time, since the new cryogenic refrigerator can be lubricated without oil, the common low-temperature oil blockage failure of ultra-low temperature refrigerators using vapor compression refrigeration is eliminated, and the system is more stable and reliable. Moreover, these new cryogenic refrigerators usually use natural substances such as nitrogen and helium as refrigerants, which are more environmentally friendly. With the popularization of ultra-low temperature refrigerators, the application prospects of these new cryogenic refrigerators are more extensive. Among these new cryogenic refrigerators, Stirling refrigerators have been widely used for their simple structure, no moving parts at low temperatures, reliable operation, low vibration, and long life. . Summary of the invention

[0004] The purpose of the present invention is to address the problems of low efficiency and unreliability of the existing traditional cascade vapor compression refrigeration system, and to propose a low-temperature refrigerator based on a Stirling refrigerator.

[0005] The invention comprises a refrigerator body and a refrigerator door. A freezing chamber is arranged in the refrigerator body. A heat preservation partition is arranged in the refrigerator body. The body below the heat preservation partition is a refrigeration working room. Heat dissipation holes are opened on the side of the refrigerator body where the refrigeration working room is located.

[0006] A cooling pipe is arranged at the back of the refrigerator body corresponding to the position of the freezing chamber. The cooling pipe is a serpentine copper pipe with closed ends, and the copper pipe is filled with a refrigerant medium.

[0007] A Stirling refrigerator is arranged in the refrigeration working chamber, and heat exhaust fans are arranged on both sides of the Stirling refrigerator.

[0008] The cold head of the Stirling refrigerator is arranged through the heat-insulating partition, and the cold head is connected to the cooling pipe through a flexible heat-conducting member.

[0009] The flexible heat conducting member is a flexible metal sheet or metal net, has an upper arm and a lower arm, and can produce elastic deformation in the longitudinal direction.

[0010] Furthermore, the flexible heat conducting member is an elastic body bent into a U-shape or an S-shape.

[0011] Furthermore, the lower arm of the flexible heat conducting member is welded to the cold head.

[0012] Furthermore, the bending part of the serpentine cooling pipe is distributed vertically, and the upper arm of the flexible heat conduction member is welded to one end and one side of the bending part of the cooling pipe. Alternatively, the bending part of the serpentine cooling pipe is distributed horizontally, and the upper arm of the flexible heat conduction member is welded to one end and the first straight part of the cooling pipe.

[0013] The present invention utilizes the advantages of the Stirling refrigerator, which is environmentally friendly, energy-saving, and suitable for low-temperature refrigeration. The refrigeration effect can reach more than twice that of the traditional cascade steam compression refrigeration system, solving the problems of the traditional steam compression refrigeration system being energy-saving and environmentally unfriendly. At the same time, the working fluid of the Stirling refrigerator is helium, which is pollution-free and environmentally friendly. The present invention solves the problems of the Stirling refrigerator's cold head vibrating greatly, making high noise, and having a short lifespan through a flexible heat conduction member. Compared with the existing low-temperature refrigerator, the present invention has low vibration, low cost, high heat transfer efficiency, long lifespan, and does not generate any pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is the appearance diagram of the present invention;

[0015] Figure 2 It is a schematic diagram of the back structure of the present invention;

[0016] Figure 3 is a schematic diagram of a flexible heat conducting member;

[0017] Figure 4 is a schematic diagram of another flexible heat conducting member;

[0018] Figure 5 It is a schematic diagram of the connection between the cooling tube and the flexible heat conduction member. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] like Figure 1 and 2As shown, a low-temperature refrigerator based on a Stirling refrigerator for a working temperature range of -50°C to -90°C includes a refrigerator body 1 and a refrigerator door 2, and a freezing chamber 3 is arranged in the refrigerator body 1.

[0021] A heat preservation partition 5 is arranged in the refrigerator box 1, and the box below the heat preservation partition 5 is a refrigeration working room 6. A heat dissipation hole 4 is opened on the side of the refrigerator box where the refrigeration working room 6 is located. A cooling pipe 7 is arranged at the back of the refrigerator box 1 corresponding to the position of the freezing chamber 3. The cooling pipe 7 is a serpentine copper tube with closed ends. The copper tube is filled with a refrigerant medium, such as R404A, R503, R508A, etc., and the filling rate is 30-40%.

[0022] A Stirling refrigerator 8 is provided in the refrigeration studio 6, and the working medium in the Stirling refrigerator is nitrogen. Heat exhaust fans 9 are provided on both sides of the Stirling refrigerator 8, and the heat exhaust fans 9 discharge the heat generated by the Stirling refrigerator 8 out of the refrigerator box through the heat dissipation holes 4.

[0023] The cold head 10 of the Stirling refrigerator 8 is disposed through the heat-insulating partition 5 , and the cold head 10 is connected to the cooling pipe 7 via a flexible heat-conducting member 11 .

[0024] The flexible heat conducting member 11 is a flexible metal sheet or metal mesh bent into a U-shape or an S-shape, and has two upper and lower arms 11-1 and 11-2, which can produce elastic deformation in the longitudinal direction. Figure 3 The flexible heat conducting member 11 is a flexible metal sheet bent into an S shape; Figure 4 The flexible heat conducting member 11 is a metal mesh bent into a U shape.

[0025] The lower arm 11-2 of the flexible heat conducting member 11 is welded to the cold head 10, and the upper arm 11-1 is welded to one end and one side of the bending portion of the cooling pipe 7 (when the bending portion of the cooling pipe 7 is distributed up and down, such as Figure 2 ), or the upper arm 11-1 is welded to one end of the cooling tube 7 and the first straight section (when the bending part of the cooling tube 7 is distributed left and right, such as Figure 5 ).

[0026] The cold head 10 of the Stirling refrigerator exchanges heat with the cold pipe 7 through the flexible heat conduction member 11, and the working fluid in the cold pipe 7 forms an oscillating flow, thereby bringing the cold from the cold end to the hot end. During the refrigeration process of the free piston Stirling refrigerator, the cold head 10 vibrates up and down, and the flexible heat conduction member 11 effectively reduces the vibration caused by the cold head, reduces noise, and prolongs the service life. The flexible heat conduction member 11 used has a low connection cost and a simple structure, which can achieve heat conduction while effectively reducing vibration.

[0027] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A low-temperature refrigerator based on a Stirling refrigerator, comprising a refrigerator body (1) and a refrigerator door (2), wherein a freezing chamber (3) is arranged in the refrigerator body (1), a heat-insulating partition (5) is arranged in the refrigerator body (1), a body below the heat-insulating partition (5) is a refrigeration working chamber (6), and a heat dissipation hole (4) is provided on a side surface of the refrigerator body where the refrigeration working chamber (6) is located; the characteristics are: A cooling pipe (7) is arranged at the back of the refrigerator body (1) at a position corresponding to the freezing chamber (3); the cooling pipe (7) is a serpentine copper tube with closed ends, and the copper tube is filled with a refrigerant medium, and the filling rate is 30-40%; a Stirling refrigerator (8) is arranged in the refrigeration working room (6), and heat exhaust fans (9) are arranged on both sides of the Stirling refrigerator; the cold head (10) of the Stirling refrigerator is arranged through the heat preservation partition (5), and the cold head (10) is connected to the cooling pipe (7) through a flexible heat conduction member (11); the flexible heat conduction member (11) is a flexible metal sheet or metal mesh, having an upper arm (11-1) and a lower arm (11-2), and can produce elastic deformation in the longitudinal direction; The flexible heat conducting member (11) is an elastic body bent into a U-shape or an S-shape; The lower arm (11-2) of the flexible heat conducting member is welded to the cold head (10); The bending parts of the serpentine cooling pipe (7) are distributed up and down, and the upper arm (11-1) of the flexible heat conducting member is welded to one end and the bending part of one side of the cooling pipe (7); Alternatively, the bending portion of the serpentine cooling pipe (7) is distributed on the left and right, and the upper arm (11-1) of the flexible heat conduction member is welded to one end of the cooling pipe (7) and the first straight portion.

Images