A liquid nitrogen cold screen device

Abstract

The application is a divisional application of application No. 2021108734357. The liquid nitrogen cold screen device of the application comprises a container shell, a cold screen device arranged in the container shell, and a fixing device for arranging the cold screen device in the container shell, the fixing device forms a spaced cavity between the cold screen device and the inner wall of the container shell, and a heat insulation film is arranged on the inner side of the cold screen device. The application provides a liquid nitrogen cold screen device, the fixing device forms a spaced cavity between the cold screen device and the inner wall of the container shell, reduces the contact between the cold screen device and the container shell, thereby reducing heat radiation, convection heat transfer and heat conduction, and further preventing heat leakage through the heat insulation film, achieving the effects of preventing heat leakage and reducing the loss of ultra-low temperature, and increasing the storage effect and storage time of ultra-low temperature.

Description

[0001] The application is a divisional application, the original application has the application number of 2021108734357, the application date is July 30, 2021, and the invention name is 'a liquid nitrogen cold screen structure'.

[0003] The application relates to the technical field of low-temperature equipment, in particular to a liquid nitrogen cold screen device.

[0005] With the development of science and technology, people's research in various fields is more and more in-depth, especially the rapidly rising biological medicine, superconducting and other industries, the development of these fields cannot be separated from the support of low temperature and ultra-low temperature. The acquisition of ultra-low temperature has become the key of many researches. At present, the acquisition of ultra-low temperature mainly relies on liquid helium, because the price of liquid helium is expensive, and the heat leakage means the increase of cost, so the requirement for the heat leakage of the equipment is extremely high, and the method of directly using liquid helium as a cold source is obviously not desirable.

[0007] The application solves the technical problem that the heat leakage of the low-temperature maintenance device leads to high cost of obtaining ultra-low temperature, and provides a liquid nitrogen cold screen device with simple structure and reasonable design.

[0008] The application is realized by the following technical scheme:

[0009] A liquid nitrogen cold screen device, comprising a container shell, a cold screen device arranged in the container shell, and a fixing device for arranging the cold screen device in the container shell, the fixing device forms a spaced cavity between the cold screen device and the inner wall of the container shell, and a heat insulation film is arranged on the inner side of the cold screen device.

[0010] The liquid nitrogen cold screen device, the cold screen device comprises a frame, and a side plate arranged on the side and bottom surface of the frame.

[0011] The liquid nitrogen cold screen device, the cold screen device further comprises a copper pipe arranged on the inner side of the side plate, and a connecting piece for riveting the side plate to fix the copper pipe, and the connecting piece is attached to the outer wall of the copper pipe.

[0012] The liquid nitrogen cold screen device, the copper pipe is integrally formed, the copper pipe comprises a horizontal section attached to the side plate and extending in the horizontal direction, and the distance between adjacent two horizontal sections is the same.

[0013] The liquid nitrogen cold screen device further comprises an adjusting device for adjusting the spacing distance between the cold screen device and the side plate.

[0014] ​​​The liquid nitrogen cold screen device as claimed in claim 1, wherein the adjusting device comprises a first fixed pipe arranged on the frame, a second fixed pipe arranged on the inner side wall of the container shell and used for supporting the first fixed pipe, a first limiting block arranged on the first fixed pipe, and a second limiting block arranged on the second fixed pipe.

[0015] The liquid nitrogen cold screen device as claimed in claim 1, wherein the first fixed pipe and the second fixed pipe are circular pipes.

[0016] The liquid nitrogen cold screen device as claimed in claim 1, further comprising an upper cover matched with the container shell, and the cold screen device further comprises a cold screen top plate arranged on the top opening of the frame, and the upper cover is provided with a lifting device used for lifting the cold screen top plate out of the container shell after the upper cover is separated from the container shell.

[0017] The liquid nitrogen cold screen device as claimed in claim 1, wherein the cold screen top plate is provided with a through hole, the lifting device comprises a lifting rod connected with the upper cover and used for penetrating through the through hole, and a supporting plate arranged on the lifting rod, and the lifting rod is pulled out through the through hole to the supporting plate to press on the bottom of the cold screen top plate to lift the cold screen top plate.

[0018] The liquid nitrogen cold screen device as claimed in claim 1, wherein a levelness adjusting device is arranged between the lifting device and the upper cover, and the levelness adjusting device is used for adjusting the levelness of the supporting plate when the supporting plate is lifted.

[0019] Compared with the prior art, the present application has the following advantages:

[0020] The present application provides a liquid nitrogen cold screen device, which comprises a container shell, a cold screen device arranged in the container shell, and a fixing device for arranging the cold screen device in the container shell, the fixing device forms a spaced cavity between the cold screen device and the inner wall of the container shell, and a heat insulation film is arranged on the inner side of the cold screen device. The fixing device forms a spaced cavity between the cold screen device and the inner wall of the container shell, reduces the contact between the cold screen device and the container shell, thereby reducing heat radiation, convection heat transfer and heat conduction, and further preventing heat leakage through the heat insulation film, achieving the effects of preventing heat leakage and reducing the loss of ultra-low temperature, and increasing the storage effect and storage time of ultra-low temperature. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort based on these drawings.

[0023] Figure 1 is a structural schematic diagram of the present application.

[0024] Figure 2 is a schematic diagram of the internal structure of the present application;

[0025] Figure 3 is a top view of the present application;

[0026] Figure 4 is Figure 3 a sectional view at A-A of

[0027] Figure 5 is Figure 3 a sectional view at B-B of

[0028] Figure 6 is a partial sectional view of the side plate.

DETAILED DESCRIPTION

[0030] In order to make the technical problems solved by the present application, technical solutions and beneficial effects more clearly understood, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application.

[0031] When the embodiments of the present application refer to "first", "second", etc. ordinal numbers, unless it is clear from the context that it expresses the order, it should be understood that it is merely used for distinction.

[0032] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0033] A liquid nitrogen cold screen device, comprising a container shell 1, a cold screen device 2 arranged in the container shell 1, and a fixing device for erecting the cold screen device 2 in the container shell 1, the fixing device forms a spaced cavity 4 between the cold screen device 2 and the inner wall of the container shell 1, and a heat insulation film 8 is arranged on the inner side of the cold screen device 2. In the embodiment, the heat insulation film is an aluminum film with extremely high reflectivity, which can not only reduce heat radiation heat transfer, but also ensure uniform cooling of the copper plate and reduce the convective cooling loss caused by the layout temperature difference.

[0034] The embodiment of the present application provides a liquid nitrogen cold screen device, which comprises a container shell, a cold screen device arranged in the container shell, and a fixing device for arranging the cold screen device in the container shell, the fixing device forms a spaced cavity between the cold screen device and the inner wall of the container shell, and a heat insulation film is arranged on the inner side of the cold screen device. The fixing device forms a spaced cavity between the cold screen device and the inner wall of the container shell, reduces the contact between the cold screen device and the container shell, thereby reducing heat radiation, convection heat transfer and heat conduction, and further preventing heat leakage through the heat insulation film, so that the effect of preventing heat leakage and reducing the loss of ultralow temperature is achieved, and the storage effect and storage time of the ultralow temperature are increased.

[0035] Further, as a preferred embodiment of the present application but not limited, the cold screen device 2 comprises a frame 21 and a side plate 22 arranged on the side and bottom surface of the frame 21. The side plate in the embodiment is a copper plate, and the frame is a whole frame, the copper plate is arranged on the outer side of the frame and is fixed to the frame by rivets, and the manufacturing is convenient.

[0036] Further, as a preferred embodiment of the present application but not limited, the cold screen device 2 further comprises a copper pipe 23 arranged on the inner side of the side plate 22 and a connecting piece 24 riveted to the side plate 22 to fix the copper pipe 23, and the connecting piece 24 is attached to the outer wall of the copper pipe 23. The copper pipe and the copper plate are riveted to the copper plate through the connecting piece with the same curvature as the copper pipe, and the contact area of the copper pipe and the copper plate enables the cold energy to be quickly dispersed.

[0037] Further, as a preferred embodiment of the present application but not limited, the copper pipe 23 is integrally formed, and the copper pipe 23 comprises a horizontal section 231 attached to the side plate 22 and extending in the horizontal direction, and the distance between adjacent two horizontal sections 231 is the same. The copper pipe is made of a whole coil, and the easy formability of copper is used to avoid welding between the copper pipes and reduce the leakage of the pipeline. The copper pipe arranged in a snake shape on the inner side of the copper plate enables the cold energy to be uniformly distributed.

[0038] Further, as a preferred embodiment of the present application but not limited, the cold screen device 2 further comprises a cold screen top plate 25 arranged on the top opening of the frame 21, and a bending part 251 is arranged on the top surface of the side plate 22 and used for attaching to the bottom surface of the cold screen top plate 25. The bending part is used for increasing the strength of the side plate, and the bending part on the top surface of the side plate enables the cold screen top plate to directly contact the side plate and transfer the cold energy to the cold screen top plate.

[0039] Further, as a preferred embodiment of the present application but not limited, the adjusting device 5 for adjusting the distance between the cold screen device 2 and the side plate 22 is further included.

[0040] Further, as a preferred embodiment of the present application but not limited, the adjusting device 5 comprises a first fixed tube 51 arranged on the frame 21, a second fixed tube 52 arranged on the inner side wall of the container shell 1 and used for supporting the first fixed tube 51, a first limiting block 53 arranged on the first fixed tube 51, and a second limiting block 54 arranged on the second fixed tube 52. The positioning of the whole cold shield device is completed by adjusting the first limiting block and the second limiting block. The first limiting block and the second limiting block are made of G10 material with extremely low thermal conductivity, and the first fixed tube arranged on the container shell is long enough to increase the heat transfer length. The whole design can reduce the heat conduction to a very low level.

[0041] Further, as a preferred embodiment of the present application but not limited, the first fixed tube 51 and the second fixed tube 52 are both circular tubes. The use of circular tubes makes the contact between the first fixed tube and the second fixed tube be point contact, which can reduce the contact area.

[0042] Further, as a preferred embodiment of the present application but not limited, the upper cover 6 cooperating with the container shell 1 is further included, and the upper cover 6 is provided with a lifting device 7 used for lifting the cold shield top plate 25 out of the container shell 1 after the upper cover 6 is separated from the container shell 1.

[0043] Further, as a preferred embodiment of the present application but not limited, the cold shield top plate 25 is provided with a through hole 252, the lifting device 7 comprises a lifting rod 71 connected with the upper cover 6 and used for penetrating through the through hole 252, and a supporting plate 72 arranged on the lifting rod 71, and the lifting rod 71 penetrates through the through hole 252 and is pulled out to the supporting plate 72 which is pressed on the bottom of the cold shield top plate 25 to lift the cold shield top plate 25. Four lifting rods are connected with the upper cover through flanges, and the longer the lifting rod is, the lower the heat leakage caused by the lifting rod is. The through hole ensures that the lifting rod does not contact the cold shield top plate. When the upper cover is lifted, only the cold shield top plate is lifted, and other structures are not moved, which facilitates the maintenance in the later period and the replacement of the test equipment.

[0044] Further, as a preferred embodiment of the present application but not limited, the container shell 1 is provided with a vacuum port 11. The inside of the whole container shell is vacuumized to block the convection heat transfer.

[0045] Further, as a preferred embodiment of the present application but not limited, a levelness adjusting device is arranged between the lifting device 7 and the upper cover 6, and the levelness adjusting device is used for adjusting the levelness of the supporting plate 72 when the supporting plate 72 is lifted. The nuts arranged on the upper and lower ends of the lifting rod can be used to adjust the levelness of the installation to meet the installation of the equipment with levelness requirement.

[0046] Furthermore, as a preferred embodiment of this solution and not a limitation, the outer side of the side plate is also provided with thermal insulation material 81. The thermal insulation material has a multi-layer structure with 20 to 25 layers.

[0047] Furthermore, as a preferred embodiment of this solution and not a limitation, the insulation material includes multiple insulation layers, each with through holes. The through holes on adjacent insulation layers are staggered. The through holes can be made using a pin. The through holes prevent both convective and radiative heat loss without reducing the efficiency of the vacuum pump.

[0048] Furthermore, as a preferred embodiment of this solution, and not a limitation thereof, the copper tube is provided with a VCR connector hose 12 at its inlet and outlet. The reliability of the VCR connector seal is utilized, and the hose facilitates the removal of the internal core.

[0049] Furthermore, as a preferred embodiment of this solution and not a limitation, the lifting device further includes a mounting bracket 73 connecting the ends of the plurality of lifting rods, with a G10 pad 74 and a PTFE gasket 75 provided between the lifting rods and the mounting bracket. This reduces direct contact between the lifting rods and the mounting bracket, thereby reducing heat leakage.

[0050] Furthermore, as a preferred embodiment of this solution, and not a limitation thereof, it also includes safety valves and regulating valves located at the inlet and outlet of the liquid nitrogen. The safety valves ensure pipeline safety. A thermometer is installed on the cold shield device to detect the cold shield temperature and regulate the liquid nitrogen supply flow rate.

[0051] The working principle of this embodiment is as follows:

[0052] This invention provides a liquid nitrogen cooling shield device, including a container shell, a cooling shield device disposed within the container shell, and a fixing device for mounting the cooling shield device within the container shell. The fixing device creates a spacer cavity between the cooling shield device and the inner wall of the container shell. This spacer cavity reduces contact between the cooling shield device and the container shell, thereby reducing heat radiation, convection, and conduction, preventing heat leakage, reducing cryogenic losses, and increasing the effectiveness and duration of cryogenic storage.

[0053] The liquid nitrogen cold screen device provided by the embodiment of the application is economical and feasible, stable in performance, and ingenious in structure, and can provide a stable low-temperature environment for various researches. Through analysis of the basic principle of heat leakage, a liquid nitrogen cold screen device is designed by comprehensively considering heat conduction, convection and thermal radiation. When used for maintaining low temperature, the device has the effect of extremely low heat leakage. By blocking and reducing thermal radiation, convection heat transfer and heat conduction, the consumption of liquid helium for maintaining ultra-low temperature inside can be greatly reduced, thereby reducing the operation cost of the liquid nitrogen cold screen device. The upper and lower separation effect brought by the lifting device is easy for later maintenance and replacement of the test device. The device can be widely applied to various fields requiring low-temperature environment maintenance, such as scientific research, military and medical treatment.

[0054] The above is the embodiment provided in combination with specific content, and it is not considered that the specific implementation of the application is limited to the description. Any similar structure or method as the application, or any technical deduction or replacement made on the basis of the concept of the application, should be considered as the protection scope of the application.

Claims

1. A liquid nitrogen cooling screen device, characterized in that: Includes a container shell (1), a cold shield device (2) disposed in the container shell (1), and a fixing device for mounting the cold shield device (2) in the container shell (1), wherein the fixing device causes the cold shield device (2) to form a spaced cavity (4) with the inner wall of the container shell (1), and the inner side of the cold shield device (2) is covered with a heat insulation film (8). The cold screen device (2) includes a frame (21) and side plates (22) laid on the periphery and bottom surface of the frame (21). The cold screen device (2) further includes a copper tube (23) disposed on the inner side of the side plate (22), and a connector (24) riveted to the side plate (22) to fix the copper tube (23), the connector (24) being attached to the outer wall of the copper tube (23); The copper tube (23) is integrally formed, and the copper tube (23) includes a horizontal segment (231) that is attached to the side plate (22) and extends in the horizontal direction, and the distance between two adjacent horizontal segments (231) is the same; It also includes an adjustment device (5) for adjusting the distance between the cold screen device (2) and the side plate (22); The adjustment device (5) includes a first fixing tube (51) disposed on the frame (21), a second fixing tube (52) disposed on the inner side wall of the container shell (1) and used to support the first fixing tube (51), a first limiting block (53) disposed on the first fixing tube (51), and a second limiting block (54) disposed on the second fixing tube (52). Both the first fixing tube (51) and the second fixing tube (52) are round tubes; It also includes an upper cover (6) that cooperates with the container shell (1), and the cold screen device (2) also includes a cold screen top plate (25) provided on the top opening of the frame (21). The upper cover (6) is provided with a lifting device (7) for pulling the cold screen top plate (25) out of the container shell (1) after it leaves the container shell (1). The cold screen top plate (25) is provided with a through hole (252). The lifting device (7) includes a lifting rod (71) connected to the upper cover (6) and used to pass through the through hole (252), and a support plate (72) provided on the lifting rod (71). The lifting rod (71) passes through the through hole (252) and is pulled out to the support plate (72) to press against the bottom of the cold screen top plate (25) to lift the cold screen top plate (25). A leveling device is provided between the lifting device (7) and the upper cover (6), and the leveling device is used to adjust the level of the pallet (72) when it is lifted. The through hole (252) prevents the hanging rod (71) from contacting the top plate (25) of the cold screen; The side plate (22) is also provided with heat insulation material (81) on the outside. The heat insulation material (81) includes multiple heat insulation layers. The heat insulation layers are provided with through holes, and the through holes on adjacent heat insulation layers are staggered. The first fixing tube (51) and the second fixing tube (52) are in point contact; The cold screen device (2) also includes a cold screen top plate (25) provided on the top opening of the frame (21), and the top surface of the side plate (22) is provided with a bent part (251) for being close to the bottom surface of the cold screen top plate (25). The lifting device (7) also includes a mounting bracket (73) that connects the ends of the plurality of lifting rods (71).

Images