A back pressure adjustable throttling refrigerator

Abstract

The present invention discloses a back-pressure adjustable throttling cooler, comprising a heat exchange channel, a throttling module, and turbine blades. The heat exchange channel comprises a high-pressure section and a low-pressure section arranged adjacent to each other, and the heat exchange channel is filled with a heat exchange medium. A throttling nozzle is formed on the throttling module to connect the outlet of the high-pressure section and the inlet of the low-pressure section. The turbine blades are rotatably arranged at the outlet of the low-pressure section. Since the turbine blades are rotatably arranged in the low-pressure section, the heat exchange medium pushes the turbine blades to perform work when flowing through the turbine blades, so that a pressure drop is formed before and after the heat exchange medium passes through the turbine blades. Since the pressure behind the turbine blades is constant at atmospheric pressure, the work of the turbine blades can increase the back pressure at the low-pressure section. When the back pressure of the low-pressure section changes, the heat exchange medium after passing through the throttling nozzle can reach the gas-liquid two-phase region at the designed back pressure and work stably at the temperature of the two-phase region corresponding to the back pressure, thereby achieving stable refrigeration temperature regulation, thereby improving the imaging quality of the infrared detector.

Description

Technical Field

[0001] The invention relates to the technical field of refrigeration, in particular to a back pressure adjustable throttling refrigerator. Background Art

[0002] Existing fixed-hole throttling coolers use high-pressure gas cylinders to supply air, utilizing the throttling effect to cool the two-phase point temperature under atmospheric back pressure. Due to their advantages such as fast cooling time, compact size, and low electromagnetic interference, they are widely used in the field of infrared guidance. However, with the advent of high-temperature infrared chips, refrigerated infrared detectors have higher cooling temperature requirements for the cooler. Existing fixed-hole throttling coolers cannot control the back pressure of the expansion chamber, and therefore cannot purposefully adjust the cooler's stable cooling temperature. Consequently, they cannot accurately match the required cooling temperature of the infrared detector chip, affecting the infrared detector's imaging quality. Summary of the Invention

[0003] In view of the above problems, the present invention provides a back pressure adjustable throttling cooler that overcomes the above problems or at least partially solves the above problems, which can solve the problem that the back pressure cannot be adjusted in the prior art and achieve the effect of improving the imaging quality of the infrared detector.

[0004] Specifically, the present invention provides a back pressure adjustable throttling refrigerator, comprising:

[0005] The heat exchange channel comprises a high-pressure section and a low-pressure section arranged adjacent to each other, and the heat exchange channel is filled with a heat exchange medium;

[0006] a throttling module, wherein a throttling nozzle is formed on the throttling module for connecting the outlet of the high-pressure section and the inlet of the low-pressure section;

[0007] Turbine blades are rotatably arranged at the outlet of the low-pressure section.

[0008] Optional, back pressure adjustable throttling cooler also includes:

[0009] The high-pressure section of the heat exchange channel is a heat exchange tube, the heat exchange tube is spirally wound on the core shaft, and the throttling module is provided at the top of the core shaft;

[0010] A Dewar trap, wherein the Dewar trap is sleeved on the outside of the core shaft, the gap between the Dewar trap, the heat exchange tube and the core shaft constitutes a low-pressure section of the heat exchange flow channel, and the outlet of the low-pressure section is annular;

[0011] The turbine blades are arranged in an annular shape at the outlet of the low-pressure section.

[0012] Optional, back pressure adjustable throttling cooler also includes:

[0013] The bottom flange is provided with the core shaft on the bottom flange, the bottom of the Dewar well is connected to the bottom flange, and the turbine blades are connected to the bottom flange through bearings.

[0014] Optionally, the bottom flange is provided with at least one notch corresponding to the position of the turbine blade, and the notch is connected to the outside atmosphere.

[0015] Optionally, the Dewar trap includes:

[0016] A Dewar cold plate, the Dewar cold plate being spaced apart and arranged above the throttling module;

[0017] A cold finger cylinder, which is fixedly connected to the Dewar cold plate and sleeved on the outside of the core shaft;

[0018] The low-pressure section includes an expansion chamber located between the throttling module and the Dewar cold plate, and a countercurrent flow channel located between the cold finger cylinder and the core shaft and the heat exchange tube.

[0019] Optionally, the Dewar trap further comprises:

[0020] A Dewar shell is sleeved on the outside of the cold finger cylinder, and a vacuum is set between the Dewar shell and the cold finger cylinder.

[0021] Optionally, a working medium inlet connected to the high-pressure section is provided on the bottom flange to introduce the heat exchange working medium into the high-pressure section.

[0022] Optionally, the working medium inlet is connected to at least two high-pressure pipelines, and each of the high-pressure pipelines is connected to the high-pressure section.

[0023] Optionally, there are multiple turbine blades, each of which extends radially along the low-pressure section outlet, and the multiple turbine blades are evenly and spaced apart along the circumference of the low-pressure section outlet.

[0024] Optionally, a threaded hole is provided at the bottom of the Dewar well, and the Dewar well and the flange are detachably connected via the threaded hole and bolts.

[0025] The beneficial effects of the present invention are:

[0026] In the back-pressure adjustable throttling refrigerator provided by the present invention, since turbine blades are rotatably provided in the low-pressure section, when in use, the heat exchange medium flows through the turbine blades and pushes the turbine blades to rotate around the turbine blade rotor to perform work, resulting in a pressure drop before and after the heat exchange medium passes through the turbine blades. Since the pressure behind the turbine blades is constant at atmospheric pressure, the turbine blade rotor can increase the back pressure in the low-pressure section by increasing the pressure in front of the turbine blades. When the back pressure in the low-pressure section changes, the heat exchange medium after passing through the throttling nozzle can reach the gas-liquid two-phase region at the designed back pressure and operate stably at the temperature of the two-phase region corresponding to the back pressure, achieving stable refrigeration temperature regulation, thereby improving the imaging quality of the infrared detector.

[0027] Furthermore, since the low-pressure section is formed between the Dewar trap, the heat exchange tube and the core shaft, the heat exchange medium is cooled by the throttling nozzle and then exchanges heat with the high-pressure heat exchange medium in the heat exchange tube through the tube wall of the heat exchange tube, so that the high-pressure heat exchange medium can be further pre-cooled, and the temperature of the heat exchange medium after throttling is continuously reduced, eventually reaching thermodynamic balance and realizing stable refrigeration.

[0028] Based on the following detailed description of specific embodiments of the present invention in conjunction with the accompanying drawings, those skilled in the art will become more aware of the above and other objects, advantages and features of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Hereinafter, some specific embodiments of the present invention will be described in detail in an exemplary and non-limiting manner with reference to the accompanying drawings. The same reference numerals in the accompanying drawings indicate the same or similar components or parts. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the accompanying drawings:

[0030] Figure 1 is a schematic structural diagram of a back pressure adjustable throttling refrigerator according to one embodiment of the present invention;

[0031] Figure 2 is a schematic cross-sectional view of a back pressure adjustable throttling refrigerator according to one embodiment of the present invention;

[0032] Figure 3 is a schematic partial structural diagram of a back pressure adjustable throttling refrigerator according to an embodiment of the present invention;

[0033] Figure 4 1 is a schematic partial structural diagram of a back pressure adjustable throttling refrigerator according to an embodiment of the present invention.

[0034] In the figure: 1. Dewar cold plate, 2. throttling nozzle, 3. heat exchange tube, 4. cold finger cylinder, 5. core shaft, 6. turbine blade, 7. bottom flange, 8. bearing, 9. working fluid inlet, 10. notch. DETAILED DESCRIPTION

[0035] Refer to the following Figures 1 to 4 To describe the back pressure adjustable throttling refrigerator of an embodiment of the present invention. In the description of this embodiment, it should be understood that the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features, that is, include one or more of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. When a feature "includes or contains" one or some of the features it covers, unless otherwise specifically described, this indicates that other features are not excluded and may further include other features.

[0036] Unless otherwise expressly defined or limited, terms such as "disposed," "installed," "connected," "connected," "fixed," and "coupled" should be broadly interpreted. For example, they may refer to fixed or detachable connections, or integration; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two elements or interaction between two elements, unless otherwise expressly defined. A person of ordinary skill in the art should be able to understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0037] In addition, in the description of this embodiment, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact via another feature between them. That is, in the description of this embodiment, the first feature being "above," "above," and "above" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature being "below," "below," or "below" the second feature may mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0038] In the description of the present embodiment, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "example," "specific example," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any appropriate manner in any one or more embodiments or examples.

[0039] The fixed-hole throttling refrigerator in the existing technology uses a high-pressure gas cylinder to supply gas and utilizes the throttling effect to cool the two-phase point temperature under atmospheric back pressure. It is impossible to adjust the back pressure of the expansion chamber, and therefore it is impossible to purposefully adjust the stable cooling temperature of the refrigerator. Its cooling temperature is generally fixed to the two-phase zone temperature of the refrigerant at normal pressure (101325Pa), which cannot accurately match the required cooling temperature of the infrared detector chip, affecting the imaging quality of the detector.

[0040] Based on this, the back pressure adjustable throttling cooler provided by the present invention can adjust the cooling temperature as needed to match the required cooling temperature of the infrared detector chip without replacing the common refrigerant, thereby improving the imaging quality. Figure 1 FIG. 1 is a schematic structural diagram of a back pressure adjustable throttling refrigerator according to an embodiment of the present invention. Figure 1 As shown, and reference Figures 2 to 4 An embodiment of the present invention provides a back-pressure adjustable throttling refrigerator, comprising a heat exchange channel, a throttling module and a turbine blade 6. The heat exchange channel comprises a high-pressure section and a low-pressure section arranged adjacent to each other, and the heat exchange channel is filled with a heat exchange medium; a throttling nozzle 2 is formed on the throttling module to connect the outlet of the high-pressure section and the inlet of the low-pressure section; the turbine blade 6 is rotatably arranged at the outlet of the low-pressure section.

[0041] In the embodiment of the present invention, since turbine blades 6 are rotatably provided in the low-pressure section, when in use, the heat exchange medium flows through the turbine blades 6 and pushes the turbine blades 6 to rotate around the rotor of the turbine blades 6 to perform work, so that a pressure drop is formed before and after the heat exchange medium passes through the turbine blades 6. Since the pressure behind the turbine blades 6 is constant at atmospheric pressure, the rotor of the turbine blades 6 can increase the back pressure in the low-pressure section by increasing the pressure in front of the turbine blades 6. When the back pressure in the low-pressure section changes, the heat exchange medium after passing through the throttling nozzle 2 can reach the gas-liquid two-phase region at the designed back pressure and operate stably at the temperature of the two-phase region corresponding to the back pressure, thereby achieving stable refrigeration temperature regulation, thereby improving the imaging quality of the infrared detector.

[0042] The back-pressure adjustable throttling cooler provided in an embodiment of the present invention can increase the stable cooling temperature of common refrigerants such as nitrogen from about 77K to about 100K, shorten the time it takes for the infrared detector to cool down to the stable cooling stage after startup, and expand the scope of use of the refrigerant to rapid cooling scenarios in higher temperature areas.

[0043] In some embodiments of the present invention, Figure 1 、 Figure 4As shown, the back-pressure adjustable throttling cooler also includes a core shaft 5 and a Dewar trap. The high-pressure section of the heat exchange flow path is the heat exchange tube 3, which is spirally coiled around the core shaft 5. The throttling module is located at the top of the core shaft 5. The Dewar trap is sleeved on the outside of the core shaft 5. The gap between the Dewar trap, the heat exchange tube 3, and the core shaft 5 constitutes the low-pressure section of the heat exchange flow path. The outlet of the low-pressure section is annular. Turbine blades 6 are arranged in an annular shape at the outlet of the low-pressure section.

[0044] In the embodiment of the present invention, since the heat exchange tube 3 is spirally coiled around the core shaft 5, the height of the preset core shaft 5 can be reduced while ensuring that the heat exchange tube 3 has a certain length, thereby meeting the design requirements of miniaturization. The heat exchange tube 3 is the high-pressure section of the heat exchange flow channel, which carries the heat exchange medium. When the heat exchange medium flows through the throttling nozzle 2, a sudden pressure change occurs, which in turn causes the temperature to drop, achieving the purpose of cooling. At the same time, because the low-pressure section is formed between the Dewar well, the heat exchange medium 3, and the core shaft 5, after being cooled by the throttling nozzle 2, heat is exchanged with the high-pressure heat exchange medium in the heat exchange tube through the tube wall of the heat exchange tube 3, further pre-cooling the high-pressure heat exchange medium and continuously reducing the temperature of the heat exchange medium after throttling, ultimately reaching thermodynamic equilibrium and achieving stable cooling. According to numerous experiments, during the startup cooling process of a fixed-hole throttling refrigerator, the cooling rate is relatively fast before the temperature reaches 150K, but the cooling rate decreases sharply after reaching 150K. Pre-cooling the high-pressure heat exchange medium can increase the refrigeration temperature to above 100K, thereby greatly shortening the time consumption of the cooling rate reduction in the later stage of cooling, greatly shortening the cooling time and the startup time of the detector.

[0045] The core shaft 5 is tapered, and the heat exchange tubes 3 are spirally wound around the outer circumference of the core shaft 5. It is understood that the heat exchange tubes 3 can be wound around the outer circumference of the core shaft 5, for example, with the end of one loop of heat exchange tubes 3 being the starting point of another loop, and with no gaps between any two loops of heat exchange tubes 3. This can extend the length of heat exchange tubes 3 that can be wound around the core shaft 5, thereby improving the cooling efficiency of the throttling refrigerator.

[0046] In some embodiments of the present invention, Figures 1 to 3 As shown, the back-pressure adjustable throttling cooler further includes a bottom flange 7, a core shaft 5 is disposed on the bottom flange 7, the bottom of the Dewar trap is connected to the bottom flange 7, and the turbine blades 6 are connected to the bottom flange 7 via bearings 8. Furthermore, at least one notch 10 is provided on the bottom flange 7 corresponding to the position of the turbine blades 6. The notch 10 is connected to the outside atmosphere to guide the heat exchange medium flowing through the turbine blades 6 out of the back-pressure adjustable throttling cooler.

[0047] In some embodiments of the present invention, the Dewar trap includes a Dewar cold plate 1 and a cold finger cylinder 4, and the Dewar cold plate 1 is arranged above the throttling module; the cold finger cylinder 4 is fixedly connected to the Dewar cold plate 1 and is sleeved on the outside of the core shaft 5; the low-pressure section includes an expansion chamber located between the throttling module and the Dewar cold plate 1, and a countercurrent flow channel located between the cold finger cylinder 4, the core shaft 5 and the heat exchange tube 3.

[0048] In the embodiment of the present invention, after the Dewar trap is coupled to the core shaft 5, an expansion chamber is formed between the Dewar cold plate 1 and the throttling nozzle 2, so that the rotor of the turbine blade 6 increases the pressure in front of the turbine blade 6, thereby increasing the back pressure at the expansion chamber. When the back pressure at the expansion chamber changes, the heat exchange medium after passing through the throttling nozzle 2 can reach the gas-liquid two-phase region at the designed back pressure and operate stably at the temperature of the two-phase region corresponding to the back pressure, thereby achieving stable refrigeration temperature regulation. At the same time, the inner wall surface of the cold finger cylinder 4 and the outer surface of the heat exchange tube 3 are in contact to form a low-pressure countercurrent flow channel, so that after the heat exchange medium is cooled by the throttling nozzle 2, it exchanges heat with the high-pressure heat exchange medium in the heat exchange tube 3 through the wall of the heat exchange tube 3, so that the high-pressure medium can be further pre-cooled and the temperature of the medium after throttling is continuously reduced, ultimately reaching thermodynamic equilibrium and achieving stable refrigeration.

[0049] In some embodiments of the present invention, the low-pressure section is provided with a back-pressure regulating mechanism, which is used to regulate the flow of the heat exchange medium in the low-pressure section. The back-pressure regulating mechanism includes a valve plate, which is in the shape of a cone ring; the conical surface of the valve plate contacts the large end of the inner wall of the cold finger cylinder 4 to form an exhaust port back-pressure valve. Specifically, the root of the inner wall of the Dewar cylinder contacts the conical surface of the conical ring valve plate of the integrated spring conical ring valve pressure regulating mechanism to form the exhaust port back-pressure valve. This arrangement makes the overall structure of the infrared detector simple and reliable. The back-pressure regulating mechanism consists of a valve plate and a spring, and the bottom flange 7 and the cold finger cylinder 4 are cleverly used to form a conical ring back-pressure valve structure.

[0050] Furthermore, the Dewar trap further comprises a Dewar shell, which is sleeved on the outside of the cold finger cylinder 4 , and a vacuum is set between the Dewar shell and the cold finger cylinder 4 to prevent heat leakage from the Dewar trap.

[0051] In some embodiments of the present invention, a working medium inlet 9 is provided on the bottom flange, communicating with the high-pressure section, for introducing the heat exchange working medium into the high-pressure section. Furthermore, the working medium inlet 9 is connected to at least two high-pressure pipelines, each of which is connected to the high-pressure section. The heat exchange tube 3 and the high-pressure pipeline are mechanically connected, for example, by threading, clamping, or welding.

[0052] In some embodiments of the present invention, Figure 2 、 Figure 3As shown, there are multiple turbine blades 6, each extending radially from the low-pressure section outlet. The multiple turbine blades 6 are evenly and spaced apart along the circumference of the low-pressure section outlet. This arrangement allows the turbine blades 6 to rotate within the low-pressure section outlet about the center of the low-pressure section outlet, thereby generating work as the heat exchange medium rotates.

[0053] In some embodiments of the present invention, a threaded hole is provided at the bottom of the Dewar well, and the Dewar well is detachably connected to the bottom flange 7 by bolts.

[0054] So far, the technical solutions of the present invention have been described in conjunction with the above multiple embodiments. However, it is easy for those skilled in the art to understand that the scope of protection of the present invention is not limited to these specific embodiments. Without departing from the technical principles of the present invention, those skilled in the art may split and combine the technical solutions in the above various embodiments, and may also make equivalent changes or replacements to the relevant technical features. Any changes, equivalent replacements, improvements, etc. made within the technical concept and / or technical principles of the present invention will fall within the scope of protection of the present invention.

Claims

1. A back pressure adjustable throttling refrigerator, characterized in that: include: The heat exchange channel comprises a high-pressure section and a low-pressure section arranged adjacent to each other, and the heat exchange channel is filled with a heat exchange medium; a throttling module, wherein a throttling nozzle is formed on the throttling module for connecting the outlet of the high-pressure section and the inlet of the low-pressure section; a turbine blade, the turbine blade being rotatably disposed at the outlet of the low-pressure section; The high-pressure section of the heat exchange channel is a heat exchange tube, the heat exchange tube is spirally wound on the core shaft, and the throttling module is provided at the top of the core shaft; A Dewar trap, wherein the Dewar trap is sleeved on the outside of the core shaft, the gap between the Dewar trap, the heat exchange tube and the core shaft constitutes a low-pressure section of the heat exchange flow channel, and the outlet of the low-pressure section is annular; The turbine blades are arranged in an annular shape at the outlet of the low-pressure section.

2. The back pressure adjustable throttling refrigerator according to claim 1, characterized in that: Also includes: The bottom flange is provided with the core shaft on the bottom flange, the bottom of the Dewar well is connected to the bottom flange, and the turbine blades are connected to the bottom flange through bearings.

3. The back pressure adjustable throttling refrigerator according to claim 2, characterized in that: The bottom flange is provided with at least one notch corresponding to the position of the turbine blade, and the notch is communicated with the outside atmosphere.

4. The back pressure adjustable throttling refrigerator according to claim 1, characterized in that: The Dewar trap comprises: A Dewar cold plate, the Dewar cold plate being spaced apart and arranged above the throttling module; A cold finger cylinder, which is fixedly connected to the Dewar cold plate and sleeved on the outside of the core shaft; The low-pressure section includes an expansion chamber located between the throttling module and the Dewar cold plate, and a countercurrent flow channel located between the cold finger cylinder and the core shaft and the heat exchange tube.

5. The back pressure adjustable throttling refrigerator according to claim 4, characterized in that: The Dewar trap further comprises: A Dewar shell is sleeved on the outside of the cold finger cylinder, and a vacuum is set between the Dewar shell and the cold finger cylinder.

6. The back pressure adjustable throttling refrigerator according to claim 3, characterized in that: The bottom flange is provided with a working medium inlet which is in communication with the high-pressure section so as to introduce the heat exchange working medium into the high-pressure section.

7. The back pressure adjustable throttling refrigerator according to claim 6, characterized in that: The working medium inlet is connected to at least two high-pressure pipelines, and each of the high-pressure pipelines is connected to the high-pressure section.

8. The back pressure adjustable throttling refrigerator according to claim 1, characterized in that: There are a plurality of turbine blades, each of which extends radially along the low-pressure section outlet, and the plurality of turbine blades are evenly and spacedly arranged along the circumferential direction of the low-pressure section outlet.

9. The back pressure adjustable throttling refrigerator according to claim 3, characterized in that: A threaded hole is provided at the bottom of the Dewar well, and the Dewar well is detachably connected to the bottom flange via the threaded hole and bolts.

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