A liquid nitrogen biological container with a multi-degree-of-freedom centering shaft structure

Abstract

The present invention discloses a liquid nitrogen biological container with a multi-degree-of-freedom centering shaft structure, which belongs to the technical field of biological containers, and includes an inner container, wherein the inner container is provided with an outer shell, a tray is provided inside the inner container, the tray is fixedly connected with a shaft, an inner centering structure connected to the inner top wall of the inner container is provided on the shaft, a tray sleeve is provided outside the shaft, the tray sleeve is fixedly connected with the tray, and a bottom centering structure connected to the inner bottom wall of the inner container is provided on the tray sleeve, and an outer centering structure connected to the outer shell is provided on the shaft outside the outer shell. By providing the inner centering structure, the bottom centering structure and the outer centering structure, the coaxiality requirements in the welding and manufacturing process of the product can be greatly reduced, and the coaxiality requirements can be achieved by adjusting the position of the shaft.

Description

Technical Field

[0001] The invention belongs to the technical field of biological containers, and in particular relates to a liquid nitrogen biological container with a multi-degree-of-freedom centering shaft structure. Background Art

[0002] Liquid nitrogen is a liquid form of nitrogen at low temperatures. Liquid nitrogen has a wide range of uses, including rapid freezing of food, making ice cream, preserving living tissue, and conducting low-temperature physics research. Liquid nitrogen biocontainers are biocontainers that use the low-temperature properties of liquid nitrogen to preserve biological samples.

[0003] The structure of the existing liquid nitrogen biological container is mainly divided into three parts: the outer shell, the inner container (including the neck) and the freezing tray. The inner container is filled with liquid nitrogen to provide a temperature field for low-temperature preservation. The freezing tray is arranged at the bottom of the inner container to provide a freezing space for biological samples. The outer shell is used to cover the outer container and form a vacuum interlayer between the inner container to shield the convection heat exchange between the inner container and the outer shell, so that the cold in the inner container is not leaked as much as possible, so that the liquid nitrogen biological container has excellent insulation performance. However, the existing liquid nitrogen biological container still has the following problems: the tray shaft is not concentric with the inner container and the outer shell, which causes the tray to get stuck. Summary of the invention

[0004] The object of the present invention is to provide a liquid nitrogen biological container with a multi-degree-of-freedom centrifugal shaft structure, so as to solve the technical problems in the prior art such as the tray being stuck due to the non-concentricity between the tray shaft and the inner container and the outer shell.

[0005] The present invention discloses a liquid nitrogen biological container with a multi-degree-of-freedom centering rotating shaft structure, comprising an inner container, an outer shell is disposed outside the inner container, a tray is disposed inside the inner container, the tray is fixedly connected to a rotating shaft, an inner centering structure connected to an inner top wall of the inner container is disposed on the rotating shaft, a tray shaft sleeve is disposed outside the rotating shaft, the tray shaft sleeve is fixedly connected to the tray, a bottom centering structure connected to an inner bottom wall of the inner container is disposed on the tray shaft sleeve, and an outer centering structure connected to the outer shell is disposed on the rotating shaft outside the outer shell.

[0006] Furthermore, a plurality of heat-insulating supports are provided between the inner container and the outer shell.

[0007] By setting up insulation supports, ensure that the upper inner container of the tank is concentric with the outer shell.

[0008] Furthermore, the bottom and sides of the tray are closed structures.

[0009] Under working conditions, the interior of the tray is entirely low-temperature gas phase space, and a low temperature close to liquid nitrogen can be achieved when storing biological samples. The use of gas phase storage can completely isolate the biological samples from the freezing medium. By setting the bottom and sides of the tray to a closed structure, even if the box storing the biological samples is damaged, the biological samples will not be contaminated by the freezing medium.

[0010] Since the bottom and sides of the tray are closed structures, after strict calculation under working conditions, the buoyancy of the tray after filling with liquid nitrogen is basically close to the gravity of the tray and the frozen biological samples, so that the tray and the samples are suspended. At this time, the tension in the tray shaft is basically equal to zero, and the thrust ball and floating bearing ball on the upper part of the tray basically do not bear any load. When the tray is rotated to extract the biological sample, the friction of the thrust ball or the floating bearing ball is small, which can increase the service life of the floating bearing ball and the thrust ball; at the same time, the tension on the tray shaft is extremely small, and the tray shaft is only subjected to torque when the tray is rotated.

[0011] Furthermore, a load-bearing centering structure is connected to the inner centering structure.

[0012] Furthermore, the load-bearing centering structure includes a floating load-bearing ball, the floating load-bearing ball sleeve is arranged on the rotating shaft, the floating load-bearing ball sleeve is provided with a floating ball sleeve, and a gap is arranged between the floating load-bearing ball and the floating ball sleeve.

[0013] By setting the gap, the floating load-bearing ball can move in the gap, and the position of the floating load-bearing ball can be changed by the size of the buoyancy, thereby reducing the friction between the floating load-bearing ball and the floating ball sleeve and increasing the service life.

[0014] Furthermore, the upper part of the floating ball sleeve is connected to a floating groove sleeve, the lower part of the floating ball sleeve is connected to a floating seat, thrust balls are respectively arranged on the floating groove sleeve and the floating seat, a limiting plate is arranged above the floating groove sleeve, a groove plate is connected below the thrust ball at the floating seat, and the groove plate is connected to the inner centering structure.

[0015] When in use, the floating load-bearing ball moves downward or upward under the action of buoyancy. When the friction between the floating load-bearing ball and the floating ball sleeve is less than the friction between the thrust ball and the limit plate or groove plate, the thrust ball will not rotate. When the friction between the floating load-bearing ball and the floating ball sleeve is greater than the friction between the thrust ball and the limit plate or groove plate, the thrust ball starts to rotate, reducing the wear of the thrust ball.

[0016] If ice forms in the tank or the thrust ball is damaged, the thrust ball will get stuck and cannot rotate anymore, but the floating load-bearing ball will not get stuck. If the floating load-bearing ball freezes, only a small force is needed to separate the ball surface from the ice surface to avoid getting stuck. Manually rotating the tray or driving it with a motor will have a lever effect on the ball surface, allowing it to rotate with only a small force.

[0017] Furthermore, the inner centering structure includes a centering cavity, an inner ball sleeve fixedly connected to the rotating shaft is arranged in the centering cavity, a sphere is fixedly connected to the outside of the inner ball sleeve, an outer ball sleeve is connected to the outside of the sphere, an centering sleeve is sleeved on the outer ball sleeve, a plurality of inclined surfaces are arranged on the centering sleeve, each of the inclined surfaces is connected to a yoke-shaped centering block, and the yoke-shaped centering block is threadedly connected to an centering wheel.

[0018] When in use, different aligning wheels are rotated, and the aligning wheels drive the yoke-shaped aligning blocks to move up and down, thereby changing the position of the aligning sleeve in the aligning cavity, thereby changing the position of the rotating shaft in the inner container.

[0019] Furthermore, the number of the inclined surfaces is 3.

[0020] Furthermore, the bottom centering structure is a bottom spherical pair.

[0021] Furthermore, the bottom spherical surface pair, the sphere and / or the floating bearing ball are in contact with non-metallic materials respectively, and the non-metallic materials are flexible materials that are resistant to low temperatures.

[0022] By setting non-metallic materials, the noise can be effectively reduced when the pallet is rotated, avoiding the squealing caused by metal-to-metal contact during rotation.

[0023] Furthermore, the outer center-aligning structure is a flange center-aligning structure, and the flange center-aligning structure is located on the outer upper head.

[0024] By adjusting the sealing flange, it is possible to avoid jamming or noise during rotation when the shaft and the welded parts on the outer upper head are not aligned concentrically.

[0025] Furthermore, the flange aligning structure includes a conical seal connected to the rotating shaft, a compression sealing nut for compressing the conical seal is arranged above the conical seal, the conical seal is connected to an aligning sealing flange, and a conical surface matching the conical seal is arranged on the aligning sealing flange.

[0026] When in use, tighten the sealing nut, and the conical sealing surface forms a seal with the rotating shaft and the conical surface of the self-aligning sealing flange to prevent low-temperature nitrogen from overflowing and forming local low temperatures that lead to ice and water.

[0027] Furthermore, a quick limiting structure is provided on the rotating shaft below the inner centering structure.

[0028] Furthermore, the quick limiting structure includes a quick limiting seat and a quick limiting wheel cooperating therewith, the quick limiting wheel is fixedly connected to the rotating shaft, and the quick limiting seat is fixedly connected to the tray.

[0029] The quick limit structure can limit the part of the rotating shaft that is torsionally twisted when the pallet rotates to a position above the quick limit wheel position. The shaft inside the pallet shaft sleeve directly bears the tensile force but not the torque, which can effectively reduce the torsion angle generated when the shaft is twisted and improve the positioning accuracy when the pallet rotates. After the quick limit seat and quick limit wheel are installed, it is convenient to install subsequent components, with fewer welding points and easy installation. By setting the quick limit wheel, the gap between the pallet and the rotating shaft can be reduced, which makes it easier for the rotating shaft to be concentric with the inner container and the outer shell.

[0030] Furthermore, a neck cover is provided on one side of the top of the shell, and a neck is sealed and connected below the neck cover.

[0031] Furthermore, the outer wall of the neck is a corrugated structure.

[0032] By setting the outer wall of the neck to a corrugated structure, the heat leakage caused by the structure can be effectively reduced, and at the same time, jamming at the neck position during the extraction of biological samples can be avoided.

[0033] Furthermore, an exhaust pipe is provided inside the neck cover body, and the exhaust pipe is made of non-metallic material.

[0034] When the container is in use, nitrogen gas generated by gasification of liquid nitrogen due to heat transfer from the structure is discharged centrally through the exhaust pipe.

[0035] Furthermore, an anti-rotation pin is provided between the outer shell and the inner container.

[0036] The anti-rotation pin can be provided to prevent relative rotation between the outer shell and the inner container.

[0037] The beneficial effects of the present invention are:

[0038] 1. By setting the inner centering structure, the bottom centering structure and the outer centering structure, the coaxiality requirements in the welding process of the product can be greatly reduced, and the coaxiality requirements can be achieved by adjusting the position of the rotating shaft;

[0039] 2. Achieve coaxiality by adjusting the axis position of the rotating shaft to avoid jamming between the rotating shaft of the pallet and the tank body due to poor coaxiality;

[0040] 3. The lateral floating shaft structure composed of a spherical pair and a thrust ball. The spherical pair and the thrust ball can rotate at the same time or the spherical pair or the thrust ball with small friction can be rotated preferentially according to the size of the friction. This structure can always avoid the tray from getting stuck due to ball damage or icing. When the spherical pair and the thrust ball position of the shaft are frozen, the thrust ball will get stuck. However, when the tray is rotated manually or driven by a motor, the spherical surface of the spherical pair will immediately separate from the ice surface, and this structure will not get stuck. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, so they should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0042] Figure 1 Schematic diagram of the biological container structure of the present invention;

[0043] Figure 2 Schematic diagram of part Ⅰ of the biological container of the present invention;

[0044] Figure 3 Schematic diagram of part Ⅱ of the biological container of the present invention;

[0045] Figure 4 Schematic diagram of part Ⅲ of the biological container of the present invention;

[0046] Figure 5 Schematic diagram of part IV of the biological container of the present invention;

[0047] Figure 6 Schematic diagram of the neck structure of the present invention.

[0048] In the above drawings, the meanings represented by each label are as follows: 1 - inner container, 2 - outer shell, 3 - tray, 4 - rotating shaft, 5 - tray bushing, 6 - adiabatic support, 7 - centering cavity, 8 - inner ball sleeve, 9 - sphere, 10 - outer ball sleeve, 111 - centering sleeve, 11 - inclined plane, 13 - wedge-shaped centering block, 14 - centering wheel, 15 - floating bearing ball, 16 - floating ball sleeve, 17 - floating groove sleeve, 18 - floating seat, 19 - thrust ball, 20 - limit plate, 21 - groove plate, 22 - bottom spherical pair, 23 - flange centering structure, 24 - outer upper head, 25 - conical seal, 26 - compression seal nut, 27 - conical surface, 28 - centering seal flange, 29 - quick limit seat, 30 - quick limit wheel, 31 - neck cover, 32 - neck, 33 - exhaust pipe, 34 - anti-rotation pin. Specific embodiments

[0049] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0050] Example 1

[0051] A liquid nitrogen biological container with a multi-degree-of-freedom centering rotating shaft structure, and its specific structure is as Figure 1-6As shown, it includes an inner container 1, an outer shell 2 is provided outside the inner container 1, a tray 3 is provided inside the inner container 1, the tray 3 is fixedly connected to a rotating shaft 4, the rotating shaft 4 is provided with an inner centering structure connected to the inner top wall of the inner container 1, a tray sleeve 5 is provided outside the rotating shaft 4, the tray sleeve 5 is fixedly connected to the tray 3, and the tray sleeve 5 is provided with a bottom centering structure connected to the inner bottom wall of the inner container 1, and the rotating shaft 4 outside the outer shell 2 is provided with an outer centering structure connected to the outer shell 2.

[0052] By setting up the inner centering structure, the bottom centering structure and the outer centering structure, the coaxiality requirements in the product welding production process can be greatly reduced, and the coaxiality requirements can be achieved by adjusting the position of the rotating shaft.

[0053] Example 2

[0054] In this embodiment, as a preferred embodiment of the present invention, the specific structure is as follows Figure 1-6 As shown, it discloses the following improvement based on the first embodiment: a plurality of heat-insulating supports 6 are provided between the inner container 1 and the outer shell 2 .

[0055] By providing the heat insulating support 6, it is ensured that the inner container 1 and the outer shell 2 in the upper part of the tank body are concentric.

[0056] Example 3

[0057] In this embodiment, as a preferred embodiment of the present invention, the specific structure is as follows Figure 1-6 As shown, based on the embodiment 1, the following improvements are disclosed: the bottom and side of the tray 3 are closed structures, the inner centering structure is connected to a load-bearing centering structure, the load-bearing centering structure includes a floating load-bearing ball 15, the floating load-bearing ball 15 is sleeved on the rotating shaft 4, a floating ball sleeve 16 is provided outside the floating load-bearing ball 15, a gap is provided between the floating load-bearing ball 15 and the floating ball sleeve 16, a floating groove sleeve 17 is connected to the upper part of the floating ball sleeve 16, a floating seat 18 is connected to the lower part of the floating ball sleeve 16, thrust balls 19 are respectively provided on the floating groove sleeve 17 and the floating seat 18, a limiting plate 20 is provided above the floating groove sleeve 17, a groove plate 21 is connected below the thrust ball 19 at the floating seat 18, and the groove plate 21 is connected to the inner centering structure.

[0058] By setting the gap, the floating load-bearing ball 15 can move in the gap, and the position of the floating load-bearing ball 15 can be changed by the size of the buoyancy, thereby reducing the friction between the floating load-bearing ball 15 and the floating ball sleeve 16 and improving the service life.

[0059] When in use, the floating load-bearing ball 15 moves downward or upward under the action of buoyancy. When the friction force between the floating load-bearing ball 15 and the floating ball sleeve 16 is smaller than the friction force between the thrust ball 19 and the limiting plate 20 or the groove plate 21, the thrust ball 19 will not rotate. When the friction force between the floating load-bearing ball 15 and the floating ball sleeve 16 is larger than the friction force between the thrust ball 19 and the limiting plate 20 or the groove plate 21, the thrust ball 19 starts to rotate, thereby reducing the wear of the thrust ball 19.

[0060] If ice forms in the tank or the thrust ball is damaged, the thrust ball will get stuck and cannot rotate anymore, but the floating bearing ball 15 will not get stuck. If the floating bearing ball 15 is frozen, only a small force is needed to separate the ball surface from the ice surface to avoid getting stuck. Manually rotating the tray 3 or driving the motor to rotate will have a lever effect on the ball surface, and only a small force is needed to rotate it.

[0061] Example 4

[0062] In this embodiment, as a preferred embodiment of the present invention, the specific structure is as follows Figure 1-6 As shown, based on the implementation mode 3, the following improvements are disclosed: the inner centering structure includes a centering cavity 7, an inner ball sleeve 8 fixedly connected to the rotating shaft 4 is arranged in the centering cavity 7, a sphere 9 is fixedly connected to the outside of the inner ball sleeve 8, an outer ball sleeve 10 is connected to the outside of the sphere 9, a centering sleeve 11 is sleeved on the outer ball sleeve 10, and the centering sleeve 11 is provided with three inclined surfaces 12, each inclined surface 12 is connected to a yoke-shaped centering block 13, and the yoke-shaped centering block 13 is threadedly connected to an aligning wheel 14.

[0063] When in use, the different aligning wheels 14 are rotated, and the aligning wheels 14 drive the yoke-shaped aligning block 13 to move up and down, thereby changing the position of the aligning sleeve 11 in the aligning cavity 7, thereby changing the position of the rotating shaft 4 in the inner container 1.

[0064] Example 5

[0065] In this embodiment, as a preferred embodiment of the present invention, the specific structure is as follows Figure 1-6 As shown, based on the fourth embodiment, the following improvement is disclosed: the bottom centering structure is a bottom spherical pair 22; the bottom spherical pair 22, the ball 9 and the floating bearing ball 15 are all in contact with a non-metallic material, and the non-metallic material is a low-temperature resistant flexible material.

[0066] By providing non-metallic materials, the noise can be effectively reduced when the tray 3 is rotated, and squealing caused by metal-to-metal contact during rotation can be avoided.

[0067] Example 6

[0068] In this embodiment, as a preferred embodiment of the present invention, the specific structure is as follows Figure 1-6As shown, it discloses the following improvements on the basis of implementation mode 1: the external centering structure is a flange centering structure 23, and the flange centering structure 23 is located on the external upper head 24, the flange centering structure 23 includes a conical seal 25 connected to the rotating shaft 4, a clamping seal nut 26 for clamping the conical seal 25 is arranged above the conical seal 25, the conical seal 25 is connected to a centering seal flange 28, and a conical surface 27 matching the conical seal 25 is arranged on the centering seal flange 28.

[0069] By adjusting the sealing flange, it is possible to avoid the shaft 4 and the welded parts on the outer upper head 24 from being misaligned and causing jamming or noise during rotation.

[0070] When in use, tighten the sealing nut 26, and the conical sealing surface forms a seal with the rotating shaft 4 and the conical surface of the self-aligning sealing flange 28 to prevent low-temperature nitrogen from overflowing and forming local low temperatures that lead to ice and water.

[0071] Example 7

[0072] In this embodiment, as a preferred embodiment of the present invention, the specific structure is as follows Figure 1-6 As shown, it discloses the following improvement based on the first embodiment: the bottom and sides of the tray 3 are closed structures.

[0073] Under working conditions, the interior of tray 3 is entirely low-temperature gas phase space, and a low temperature close to liquid nitrogen can be obtained when storing biological samples; the use of gas phase storage can achieve complete isolation of biological samples from freezing media, and by setting the bottom and sides of tray 3 as a closed structure, even if the box storing the biological samples is damaged, the biological samples will not be contaminated by the freezing media.

[0074] Since the bottom and side of the tray 3 are closed structures, after strict calculation under working conditions, the buoyancy borne by the tray 3 after filling with liquid nitrogen is basically close to the gravity of the tray 3 and the frozen biological samples, so that the tray 3 and the samples are suspended. At this time, the tension in the rotating shaft 4 of the tray 3 is basically equal to zero, and the thrust ball and the floating bearing ball 15 on the upper part of the tray 3 are basically not subjected to load. When the tray 3 is rotated to extract the biological sample, the friction of the thrust ball or the floating bearing ball 15 is small, which can increase the service life of the floating bearing ball 15 and the thrust ball; at the same time, the rotating shaft 4 of the tray 3 is subjected to extremely small tension, and the rotating shaft 4 of the tray 3 is only subjected to torque when the tray 3 is rotated.

[0075] Example 8

[0076] In this embodiment, as a preferred embodiment of the present invention, the specific structure is as follows Figure 1-6As shown, it discloses the following improvements on the basis of implementation mode 1: a quick limiting structure is provided on the rotating shaft 4 below the inner centering structure, and the quick limiting structure includes a quick limiting seat 29 and a quick limiting wheel 30 cooperating therewith, the quick limiting wheel 30 is fixedly connected to the rotating shaft 4, and the quick limiting seat 29 is fixedly connected to the tray 3.

[0077] The quick limiting structure can limit the twisted part of the rotating shaft 4 of the tray 3 to a position above the position of the quick limiting wheel 30 when the tray 3 rotates. The shaft inside the rotating shaft 4 of the tray 3 directly bears the tensile force but not the torque, which can effectively reduce the twist angle generated when the rotating shaft 4 is twisted, and improve the positioning accuracy of the tray 3 when it rotates. After the quick limiting seat 29 and the quick limiting wheel 30 are installed, it is convenient to install subsequent components, with fewer welding points and easy installation. By setting the quick limiting wheel 30, the gap between the tray 3 and the rotating shaft 4 can be reduced, so that the rotating shaft 4 is concentric with the inner container 1 and the outer shell 2.

[0078] Example 9

[0079] In this embodiment, as a preferred embodiment of the present invention, the specific structure is as follows Figure 1-6 As shown, based on the embodiment 1, the following improvements are disclosed: the outer wall of the neck 32 is a corrugated structure, an exhaust pipe 33 is arranged inside the neck cover 31, the exhaust pipe 33 is made of non-metallic material, and an anti-rotation pin 34 is arranged between the outer shell 2 and the inner container 1.

[0080] By setting the outer wall of the neck 32 to a corrugated structure, the heat leakage caused by the structure can be effectively reduced, and at the same time, the jamming at the neck 32 during the extraction of biological samples can be avoided.

[0081] When the container is in use, nitrogen gas generated by gasification of liquid nitrogen due to heat transfer from the structure is discharged centrally through the exhaust pipe 33 .

[0082] The anti-rotation pin 34 can prevent the outer shell 2 and the inner container 1 from rotating relative to each other.

[0083] The present invention is not limited to the above-mentioned optional implementation modes. Anyone can derive other various forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, all technical solutions that fall within the scope defined by the claims of the present invention fall within the protection scope of the present invention.

Claims

1. A liquid nitrogen biological container with a multi-degree-of-freedom centering shaft structure, comprising an inner container (1), characterized in that: The inner container (1) is provided with an outer shell (2) on the outside, a tray (3) is provided inside the inner container (1), the tray (3) is fixedly connected to a rotating shaft (4), an inner centering structure connected to the inner top wall of the inner container (1) is provided on the rotating shaft (4), a tray sleeve (5) is provided on the outer shell of the rotating shaft (4), the tray sleeve (5) is fixedly connected to the tray (3), and a bottom centering structure connected to the inner bottom wall of the inner container (1) is provided on the tray sleeve (5), and an outer centering structure connected to the outer shell (2) is provided on the rotating shaft (4) outside the outer shell (2); The bottom and sides of the tray (3) are closed structures; The inner centering structure comprises a centering cavity (7), an inner ball sleeve (8) fixedly connected to the rotating shaft (4) is arranged in the centering cavity (7), a sphere (9) is fixedly connected to the outside of the inner ball sleeve (8), the sphere (9) is connected to the outside of the outer ball sleeve (10), a centering sleeve (11) is sleeved on the outer ball sleeve (10), a plurality of inclined surfaces (12) are arranged on the centering sleeve (11), each of the inclined surfaces (12) is connected to a yoke-shaped centering block (13), and the yoke-shaped centering block (13) is threadedly connected to an aligning wheel (14); The bottom centering structure is a bottom spherical pair (22); The outer center-aligning structure is a flange center-aligning structure (23), and the flange center-aligning structure (23) is located on the outer upper head (24); The inner centering structure is connected to a load-bearing centering structure, the load-bearing centering structure comprises a floating load-bearing ball (15), the floating load-bearing ball (15) is sleeved on the rotating shaft (4), a floating ball sleeve (16) is provided on the outer sleeve of the floating load-bearing ball (15), and a gap is provided between the floating load-bearing ball (15) and the floating ball sleeve (16); The upper part of the floating ball sleeve (16) is connected to a floating groove sleeve (17), and the lower part of the floating ball sleeve (16) is connected to a floating seat (18). The floating groove sleeve (17) and the floating seat (18) are respectively provided with thrust balls (19). A limit plate (20) is provided above the floating groove sleeve (17). A groove plate (21) is connected below the thrust ball (19) at the floating seat (18). The groove plate (21) is connected to the inner self-aligning structure. The floating bearing ball (15) moves downward under the action of buoyancy. Or move upward, when the friction force between the floating bearing ball (15) and the floating ball sleeve (16) is less than the friction force between the thrust ball (19) and the limit plate (20) or the groove plate (21), the thrust ball (19) will not rotate, and when the friction force between the floating bearing ball (15) and the floating ball sleeve (16) is greater than the friction force between the thrust ball (19) and the limit plate (20) or the groove plate (21), the thrust ball (19) starts to rotate, reducing the wear of the thrust ball (19).

2. The liquid nitrogen biological container with a multi-degree-of-freedom centering shaft structure according to claim 1, characterized in that: A plurality of heat-insulating supports (6) are arranged between the inner container (1) and the outer shell (2).

3. The liquid nitrogen biological container with a multi-degree-of-freedom centering shaft structure according to claim 1, characterized in that: A quick limiting structure is provided on the rotating shaft (4) below the inner centering structure.

4. The liquid nitrogen biological container with a multi-degree-of-freedom centering shaft structure according to claim 1, characterized in that: A neck cover (31) is provided on one side of the top of the shell (2), and a neck (32) is sealed and connected below the neck cover (31).

5. The liquid nitrogen biological container with a multi-degree-of-freedom centering shaft structure according to claim 4, characterized in that: The outer wall of the neck (32) is a corrugated structure.

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