A New Pulse Tube Refrigerator

Abstract

The present invention discloses a novel pulse tube refrigerator, including a cold head body and an air inlet pipe, wherein the side wall of the cold head body is provided with an air inlet pipe, the bottom of the cold head body is provided with a primary refrigeration system, a spiral pipe and an expansion chamber are provided in the cold head body, the two ends of the spiral pipe are respectively connected with the air inlet pipe and the upper end of the expansion chamber, and the bottom of the expansion chamber is connected with the primary refrigeration system; and a secondary refrigeration system is also included. A spiral pipe is provided between the air inlet pipe and the expansion chamber, and through the transition of the spiral pipe, eddy loss and total pressure loss caused by high-pressure helium directly and suddenly entering the expansion chamber from the air inlet pipe is avoided, so that the flow of high-pressure helium in the spiral pipe is close to adiabatic isentropic flow, and the flow loss is small, so as to maximize the use of the energy of the high-pressure gas source, thereby improving the efficiency of refrigeration; a primary refrigeration system and a secondary refrigeration system are provided to realize graded refrigeration and improve the refrigeration effect.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigerators, in particular to a novel pulse tube refrigerator. Background Art

[0002] New pulse tube refrigerators achieve refrigeration by adiabatically evacuating high-pressure gas. In existing pulse tube refrigerators, high-pressure helium enters the cold head and abruptly exits through the inlet pipe into a large expansion cavity. This results in significant eddy current losses and total pressure loss. Furthermore, the volume and space limitations of the expansion cavity above the cold head compromise cooling efficiency. Furthermore, the existing cold head dimensions preclude the use of a linear, gradual flow pattern, creating numerous operational inconveniences. Summary of the Invention

[0003] The object of the present invention is to provide a novel pulse tube refrigerator to solve the problems raised in the above background technology.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] A new type of pulse tube refrigerator comprises a cold head body and an air inlet pipe, an air inlet pipe is provided on the side wall of the cold head body, a first-level refrigeration system is provided at the bottom of the cold head body, the first-level refrigeration system comprises a first-level heat storage tube, a first-level heat exchanger, a first-level cold plate and a first-level pulse tube, a first-level heat storage tube, a first-level heat exchanger is provided at the bottom of the first-level heat exchanger, a first-level cold plate is provided on the first-level cold plate, a first-level pulse tube is connected to the first-level pulse tube, a first-level gas reservoir connector connected to the first-level pulse tube is provided at the top of the cold head body; a spiral pipe and an expansion chamber are provided inside the cold head body, the two ends of the spiral pipe are respectively connected to the air inlet pipe and the upper end of the expansion chamber, and the bottom of the expansion chamber is connected to the first-level heat storage tube.

[0006] As a further solution of the present invention: it also includes a secondary refrigeration system, which includes a secondary heat storage tube, a secondary heat exchanger, a secondary cold plate and a secondary pulse tube. The secondary heat storage tube is connected to the primary cold plate, and a secondary heat exchanger is provided at the bottom of the secondary heat storage tube. A secondary cold plate is provided at the bottom of the secondary heat exchanger, and a secondary pulse tube is connected to the secondary cold plate. The top of the cold head body is provided with a secondary gas reservoir connector connected to the secondary pulse tube.

[0007] As a further solution of the present invention: a two-way bifurcated channel is provided inside the first-level cold plate, and both ends of the outlet of the two-way bifurcated channel are respectively connected to the first-level pulse tube and the second-level heat storage tube.

[0008] As a further solution of the present invention: a cold head cover is provided at the upper end of the cold head body.

[0009] As a further solution of the present invention: the first-stage heat exchanger and the second-stage heat exchanger are made of oxygen-free copper plates.

[0010] As a further solution of the present invention: the primary heat exchanger and the secondary heat exchanger are made of oxygen-free copper plates through rolling and soft soldering.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] 1. A spiral pipe is set between the air inlet pipe and the expansion chamber. The transition of the spiral pipe prevents the high-pressure helium from directly and suddenly entering the expansion chamber from the air inlet pipe, which causes eddy loss and total pressure loss. The flow of high-pressure helium in the spiral pipe is close to adiabatic isentropic flow, with small flow loss, thereby maximizing the energy of the high-pressure gas source and improving the refrigeration efficiency.

[0013] 2. A primary refrigeration system and a secondary refrigeration system are provided to realize graded refrigeration. The helium is cooled by expansion. The temperature of the primary cold plate can reach 40K and the corresponding cooling capacity, and then the temperature of the secondary cold plate can reach 4K and the required cooling capacity.

[0014] 3. The primary and secondary heat exchangers are made of oxygen-free copper plates that are rolled and soldered, thereby increasing their heat exchange area, achieving excellent heat transfer and conduction performance, achieving rapid heat conduction, improving cooling effects, and being easy to manufacture and process.

[0015] 4. Since there are no reciprocating parts inside the pulse tube, the fluctuation and pulsation of the airflow have little impact, thereby reducing the vibration and interference amplitude, which is beneficial to improving the accuracy of related precision measurement experiments with magnetic fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is the external view of the new pulse tube refrigerator;

[0017] Figure 2 This is an internal view of the new pulse tube refrigerator.

[0018] In the figure: 1. Cold head body; 2. Air inlet pipe; 3. First-stage heat storage tube; 4. First-stage heat exchanger; 5. First-stage cold plate; 6. First-stage pulse tube; 7. First-stage gas reservoir connector; 8. Coiled pipe; 9. Expansion chamber; 10. Second-stage heat storage tube; 11. Second-stage heat exchanger; 12. Second-stage cold plate; 13. Second-stage pulse tube; 14. Second-stage gas reservoir connector; 15. Cold head cover. DETAILED DESCRIPTION

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0020] It should be noted that if there are directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention, they are only used to explain the relative position relationship, movement status, etc. between the various components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0021] In addition, if the descriptions of "first", "second", etc. are involved in the present invention, they are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0022] Example 1

[0023] See also Figure 1-2 A new type of pulse tube refrigerator comprises a cold head body 1 and an air inlet pipe 2, the air inlet pipe 2 is provided on the side wall of the cold head body 1, a first-level refrigeration system is provided at the bottom of the cold head body 1, the first-level refrigeration system comprises a first-level heat storage tube 3, a first-level heat exchanger 4, a first-level cold plate 5 and a first-level pulse tube 6, a first-level heat storage tube 3, a first-level heat exchanger 4 is provided at the bottom of the first-level heat exchanger 4, a first-level cold plate 5 is provided, a first-level pulse tube 6 is connected to the first-level cold plate 5, a first-level gas reservoir connector 7 connected to the first-level pulse tube 6 is provided at the top of the cold head body 1; a spiral pipe 8 and an expansion chamber 9 are provided in the cold head body 1, the two ends of the spiral pipe 8 are respectively connected to the air inlet pipe 2 and the upper end of the expansion chamber 9, and the bottom of the expansion chamber 9 is connected to the first-level heat storage tube 3;

[0024] After being compressed by the compressor, the high-pressure helium enters the spiral pipe 8 in the cold head body 1 through the air inlet pipe 2, then flows into the expansion chamber 9, flows into the first-stage heat storage pipe 3, and then enters the first-stage heat exchanger 4, and flows into the first-stage cold plate 5 through the first-stage heat exchanger 4;

[0025] The spiral pipe 8 in the cold head body 1 can reduce the total pressure loss caused by the high-pressure helium entering the pipe, so that the high-pressure helium gradually transfers to the expansion chamber 9 through the spiral pipe 8, thereby solving the problem of the high-pressure helium directly and suddenly entering the large expansion chamber 9 from the intake pipe 2, causing great eddy current loss and total pressure loss. The flow of the high-pressure helium in the spiral pipe 8 is close to adiabatic isentropic flow, with low flow loss, which can maximize the use of the energy of the high-pressure gas source, thereby improving the efficiency of refrigeration.

[0026] The novel pulse tube refrigerator also includes a two-stage refrigeration system, which includes a two-stage heat storage tube 10, a two-stage heat exchanger 11, a two-stage cold plate 12, and a two-stage pulse tube 13. The two-stage heat storage tube 10 is connected to the one-stage cold plate 5. The bottom of the two-stage heat storage tube 10 is sheathed with a two-stage heat exchanger 11. The bottom of the two-stage heat exchanger 11 is provided with a two-stage cold plate 12. The two-stage cold plate 12 is connected to the two-stage pulse tube 13. The top of the cold head body 1 is provided with a two-stage gas reservoir connector 14 connected to the two-stage pulse tube 13.

[0027] A bidirectional bifurcated channel is provided inside the first-stage cold plate 5, and both ends of the bidirectional bifurcated channel are connected to the first-stage pulse tube 6 and the second-stage heat storage tube 10 respectively;

[0028] The high-pressure helium gas flowing through the bifurcated channel to the first-level pulse tube 6 flows into the first-level gas reservoir from the first-level gas reservoir connector 7 at the other end of the first-level pulse tube 6;

[0029] The high-pressure helium gas flowing into the secondary heat storage tube 10 through the bidirectional bifurcated channel will continue to flow into the secondary heat exchanger 11, and then pass through the secondary cold plate 12. Then the high-pressure helium gas flows into the secondary pulse tube 13, and finally enters the secondary gas reservoir at the secondary gas reservoir connector 14 at the other end of the secondary pulse tube 13.

[0030] In order to further improve the heat exchange performance and cooling effect of the primary heat exchanger 4 and the secondary heat exchanger 11, the primary heat exchanger 4 and the secondary heat exchanger 11 are made of oxygen-free copper plates, which have excellent heat exchange and conduction performance, can achieve rapid heat conduction, and improve the cooling effect;

[0031] The specific manufacturing method of the primary heat exchanger 4 and the secondary heat exchanger 11 is not limited. In this embodiment, preferably, the primary heat exchanger 4 and the secondary heat exchanger 11 are made of oxygen-free copper plates by rolling and soldering, thereby increasing their heat exchange area and facilitating manufacturing and processing.

[0032] In order to ensure the sealing of the inner cavity of the cold head body 1 and prevent helium leakage from the cold head body 1 , a cold head cover 15 is provided on the upper end of the cold head body 1 .

[0033] The working principle of this embodiment is:

[0034] The high-pressure helium after compression by the compressor enters the spiral pipe 8 in the cold head body 1 through the air inlet pipe 2, then flows into the expansion chamber 9, and then flows into the first-level heat storage tube 3, and then enters the first-level heat exchanger 4, and flows into the first-level cold plate 5 through the first-level heat exchanger 4; the high-pressure helium that leads to the first-level pulse tube 6 through the two-way bifurcated channel flows into the first-level gas reservoir from the first-level gas reservoir connector 7 at the other end of the first-level pulse tube 6; the high-pressure helium that leads to the second-level heat storage tube 10 through the two-way bifurcated channel will continue to flow into the second-level heat exchanger 11, and then pass through the second-level cold plate 12, and then the high-pressure helium flows into the second-level pulse tube 13, and finally enters the second-level gas reservoir at the second-level gas reservoir connector 14 at the other end of the second-level pulse tube 13.

[0035] This novel pulse tube refrigerator has a spiral duct 8 disposed between the inlet pipe 2 and the expansion chamber 9. The transition of the spiral duct 8 prevents high-pressure helium from directly and abruptly entering the expansion chamber 9 from the inlet pipe 2, thereby preventing eddy current loss and total pressure loss. The flow of high-pressure helium in the spiral duct 8 is close to adiabatic isentropic flow with minimal flow loss, thereby maximizing the energy utilization of the high-pressure gas source and improving refrigeration efficiency. A primary refrigeration system and a secondary refrigeration system are provided to achieve staged refrigeration. After expansion and cooling, the helium can reach a temperature of 40K and a corresponding cooling capacity on the primary cold plate 5, and then achieve a temperature of 4K and the required cooling capacity on the secondary cold plate 12. The primary heat exchanger 4 and the secondary heat exchanger 11 are made of oxygen-free copper plates that are rolled and soft-soldered, thereby increasing their heat exchange area, improving heat exchange and conduction performance, achieving rapid heat conduction, improving the refrigeration effect, and being easy to manufacture and process. Since there are no reciprocating parts inside the pulse tube, the fluctuation and pulsation of the airflow have little impact, thereby reducing vibration and interference amplitude, which is beneficial to improving the accuracy of related precision measurement experiments with magnetic fields.

[0036] The above is only an embodiment of the present invention, and the common knowledge such as the specific structure and characteristics of the scheme is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A novel pulse tube refrigerator, comprising a cold head body (1) and an air inlet pipe (2), wherein the cold head body (1) is provided with an air inlet pipe (2) on its side wall, and a primary refrigeration system is provided at the bottom of the cold head body (1), wherein the primary refrigeration system comprises a primary heat storage tube (3), a primary heat exchanger (4), a primary cold plate (5) and a primary pulse tube (6), wherein a primary heat exchanger (4) is sleeved at the bottom of the primary heat storage tube (3), a primary cold plate (5) is provided at the bottom of the primary heat exchanger (4), a primary cold plate (5) is connected to the primary pulse tube (6), and a primary gas reservoir connector (7) connected to the primary pulse tube (6) is provided at the top of the cold head body (1); the characteristics are as follows: The cold head body (1) is provided with a spiral pipe (8) and an expansion chamber (9), the two ends of the spiral pipe (8) are respectively connected to the air inlet pipe (2) and the upper end of the expansion chamber (9), and the bottom of the expansion chamber (9) is connected to the first-stage heat storage pipe (3); The novel pulse tube refrigerator also includes a secondary refrigeration system, the secondary refrigeration system including a secondary heat storage tube (10), a secondary heat exchanger (11), a secondary cold plate (12) and a secondary pulse tube (13), the secondary heat storage tube (10) being connected to the primary cold plate (5), the secondary heat storage tube (10) being sleeved with a secondary heat exchanger (11) at the bottom, the secondary cold plate (12) being provided at the bottom of the secondary heat exchanger (11), the secondary cold plate (12) being connected to a secondary pulse tube (13), and the top end of the cold head body (1) being provided with a secondary gas reservoir connector (14) connected to the secondary pulse tube (13); A bidirectional bifurcated channel is provided inside the first-stage cold plate (5), and both ends of the outlet of the bidirectional bifurcated channel are respectively connected to the first-stage pulse tube (6) and the second-stage heat storage tube (10); A cold head cover (15) is provided at the upper end of the cold head body (1).

2. The novel pulse tube refrigerator according to claim 1 is characterized in that: The primary heat exchanger (4) and the secondary heat exchanger (11) are made of oxygen-free copper plates.

3. The novel pulse tube refrigerator according to claim 2 is characterized in that: The primary heat exchanger (4) and the secondary heat exchanger (11) are made of oxygen-free copper plates through rolling and soft soldering.

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