Liquid nitrogen adding device for biology laboratory

Abstract

The liquid nitrogen adding device for the biology laboratory comprises a base, a rotating plate and a clamping plate, a hydraulic cylinder is installed in the center of the top face of the base, the output end of the hydraulic cylinder is connected with a lifting installation plate, a protection barrel is fixedly installed on one side of the bottom face of the lifting installation plate, and a two-way lead screw is installed on one side of an inner cavity of the protection barrel; and one end of the bidirectional lead screw is connected with the output end of a second servo motor, a guide sliding rod is fixedly installed on the other side of an inner cavity of the protection barrel, clamping plates are symmetrically arranged in the inner cavity of the protection barrel, a connecting plate is fixedly installed on the top faces of the clamping plates, a lead screw sleeve is fixedly installed at one end of the connecting plate, and the lead screw sleeve is matched with the bidirectional lead screw. The liquid nitrogen filling device has the advantages that the rotating plate, the protective cylinder and the clamping plate are arranged, the filling container and the liquid filling head can be automatically aligned, the filling container can be automatically limited and fixed during liquid filling, operation is easy and convenient, the liquid nitrogen filling efficiency is improved, and practicability is higher.

Description

Technical Field

[0001] The utility model relates to the technical field of liquid nitrogen filling, in particular to a liquid nitrogen filling device for a biological laboratory. Background Art

[0002] Liquid nitrogen is an inert, colorless, odorless, low-viscosity, non-corrosive, non-flammable, transparent liquid with extremely low temperature. It absorbs a large amount of heat when vaporized and causes frostbite. Liquid nitrogen is usually stored in liquid nitrogen tanks or liquid nitrogen bottles. Liquid nitrogen is often used in biological experiments and tests. Biological storage liquid nitrogen tanks need to be refilled and replenished regularly. The liquid nitrogen inside needs to be replenished regularly to maintain a stable low-temperature environment and ensure the activity and integrity of the stored samples. It can be replenished by filling and adding liquid. For this purpose, a liquid nitrogen adding device for biological laboratories is required.

[0003] The prior art discloses a liquid nitrogen filling device with announcement number: CN220669157U. When the utility model is in use, the clamping mechanism installed on each storage table is used to limit and fix the liquid nitrogen filling container. However, the clamping mechanism requires the user to perform frequent manual operations when in use, which is cumbersome, time-consuming and laborious. Although the clamping mechanism can fix the filling container, it is difficult to ensure that the filling port of the filling container can be aligned with the filling head. The manual alignment of the user is cumbersome, which reduces the efficiency of liquid nitrogen filling. In view of the shortcomings of the utility model, the technicians in this field have proposed a liquid nitrogen filling device for biological laboratories. Utility Model Content

[0004] 1. Technical issues to be solved

[0005] In view of the deficiencies in the prior art, the utility model provides a liquid nitrogen adding device for a biological laboratory, which can automatically align a filling container with a filling head and can automatically limit and fix the filling container when adding liquid. The operation is simple and convenient, the liquid nitrogen adding efficiency is improved, and the utility model has the advantages of being more practical, thereby solving the problems in the above-mentioned background technology.

[0006] (II) Technical solution

[0007] In order to realize the above-mentioned automatic alignment of the filling container and the filling head, and to automatically limit and fix the filling container when adding liquid, the operation is simple and convenient, the efficiency of liquid nitrogen filling is improved, and the practicality is stronger. The specific technical scheme adopted by the utility model is as follows: a liquid nitrogen filling device for a biological laboratory, comprising a base, a rotating plate and a clamping plate, a hydraulic cylinder is installed in the center of the top surface of the base, and a lifting mounting plate is connected to the output end of the hydraulic cylinder, and a protective cylinder is fixedly installed on one side of the bottom surface of the lifting mounting plate, a bidirectional screw is installed on one side of the inner cavity of the protective cylinder, and one end of the bidirectional screw is connected to the output end of the second servo motor, a guide slide rod is fixedly installed on the other side of the inner cavity of the protective cylinder, and the inner cavity of the protective cylinder is symmetrically provided with clamping plates. The top surface of the base is provided with a rotating groove, and a rotating slip ring is fixedly installed on the bottom surface of the rotating plate, and the rotating slip ring is embedded in the rotating groove. An installation cavity is provided in the base, and a first servo motor is installed in the installation cavity, and a rotating shaft is connected to the output end of the first servo motor, a gear is fixedly installed on the rotating shaft, a gear ring is fixedly installed on the side wall of the rotating plate, and the gear ring and the gear are meshed with each other, a plurality of storage tables are evenly fixedly installed on the top surface of the rotating plate, and a storage groove is provided on the top surface of the storage table.

[0008] Furthermore, a filling pump is fixedly installed on the top surface of the lifting mounting plate, and a liquid inlet pipe is connected to one side of the filling pump, and a liquid outlet pipe is connected to the other side of the filling pump, the liquid outlet pipe is located at one end of the inner cavity of the protective tube and is connected to a filling head, and a solenoid valve is installed on the liquid outlet pipe, a temperature sensor located in the inner cavity of the protective tube is installed on the bottom surface of the lifting mounting plate, and a buzzer alarm is fixedly installed on the top surface of the lifting mounting plate.

[0009] Furthermore, a control panel is installed on the side wall of the base, and the control panel is electrically connected to the hydraulic cylinder, the first servo motor, the second servo motor, the temperature sensor, the filling pump, the solenoid valve and the buzzer alarm.

[0010] Furthermore, the central axes of the base, the hydraulic cylinder, the rotating plate, the rotating slide groove and the rotating slip ring are on the same straight line.

[0011] Furthermore, the two clamping plates are arc-shaped plates, and anti-skid rubber pads are symmetrically fixedly installed on opposite sides of the two clamping plates.

[0012] Furthermore, the inner diameter of the protective tube is larger than the diameter of the storage platform.

[0013] Furthermore, the rotating plate is an annular plate.

[0014] (III) Beneficial effects

[0015] Compared with the prior art, the utility model provides a liquid nitrogen adding device for biological laboratories, which has the following beneficial effects:

[0016] (1) The utility model is provided with a rotating plate, a protective cylinder and a clamping plate. A hydraulic cylinder is installed in the center of the top surface of the base, and a lifting mounting plate is connected to the output end of the hydraulic cylinder. A filling pump is installed on the lifting mounting plate, and a liquid inlet pipe is connected to one side of the filling pump, and a liquid outlet pipe is connected to the other side of the filling pump. A filling head is connected to one end of the liquid outlet pipe, and a rotating slide groove is provided on the top surface of the base, and a rotating slip ring fixedly installed on the bottom surface of the rotating plate is embedded in the rotating slide groove, and a plurality of storage tables are evenly fixedly installed on the top surface of the rotating plate, and a storage groove is provided on the top surface of the storage table. When in use, the user can place the filling container In the storage slot, the first servo motor installed in the installation cavity is then started through the control panel to drive the rotating shaft to rotate. Because the gear fixedly installed on the rotating shaft is meshed with the gear ring fixedly installed on the side wall of the rotating plate, the first servo motor can drive the rotating plate together with the storage platform and the filling container to rotate. When the filling container rotates to below the filling head, the control panel can start the hydraulic cylinder to drive the lifting installation plate to descend. A protective cylinder is fixedly installed on the bottom surface of the lifting installation plate. As the lifting installation plate descends, it can be sleeved on the outside of the storage platform. The inner cavity of the protective cylinder is symmetrically provided with clamping plates, and a connecting plate is fixedly installed on the top of the clamping plate, and a wire is fixedly installed at one end of the connecting plate. A rod sleeve is provided, and a two-way screw is installed on one side of the inner cavity of the protective cylinder, and one end of the two-way screw is connected to the output end of the second servo motor, and the two-way screw cooperates with the screw sleeve. On the other hand, a guide slide sleeve fixedly installed at the other end of the connecting plate is sleeved with a guide slide rod, so as the two-way screw rotates, the two clamping plates can be driven to move relative to each other until the two clamping plates push the filling container placed in the storage groove to the center position of the protective cylinder, at this time, it can be ensured that the filling port of the filling container is aligned with the filling head, after loosening the two clamping plates, the hydraulic cylinder drives the lifting mounting plate together with the filling head to continue to descend, so that the filling head is docked with the filling port of the filling container, and then the two clamping plates are used. The clamping plate equipped with a non-slip rubber pad can stably clamp the filling container to carry out the liquid nitrogen filling and replenishing operation. After the filling is completed, the hydraulic cylinder drives the lifting and mounting plate together with the protective cylinder to reset, and the rotating plate drives the storage table and the filling container to continue to rotate, so that the user can take out the filling container after the filling. Such a cycle can form a continuous operation, so as to quickly add liquid to the batch of liquid nitrogen bottles to be replenished in the biological laboratory. Therefore, a liquid nitrogen filling device for a biological laboratory can automatically realize the alignment of the filling container and the filling head, and can automatically realize the limit fixation of the filling container when adding liquid. The operation is simple and convenient, the liquid nitrogen filling efficiency is improved, and the practicality is stronger.

[0017] (2) The utility model is provided with a protective tube, a temperature sensor and a buzzer alarm. As mentioned above, when the liquid nitrogen adding operation is performed, the filling container and the filling head are located in the inner cavity of the protective tube, thereby effectively preventing the user from getting close to the liquid nitrogen and causing frostbite hazards due to accidental touching. In addition, when the liquid nitrogen leaks during the liquid nitrogen adding process, the low-temperature liquid nitrogen will also be in the inner cavity of the protective tube and will not diffuse out quickly. The bottom surface of the lifting installation plate is provided with a temperature sensor located in the inner cavity of the protective tube. When the temperature sensor detects that the temperature in the protective tube drops rapidly, it can be known that a leakage has occurred during the liquid nitrogen adding process, and the signal can be fed back to the control panel. At this time, the control panel can stop the filling pump and simultaneously close the solenoid valve installed on the liquid outlet pipe, and start the installed buzzer alarm to sound an alarm, so as to remind the user to handle it in time, prevent the risk of accidents and reduce the loss of liquid nitrogen, thereby ensuring the safety of the use of the liquid nitrogen adding device in the biological laboratory and making it more practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a structural schematic diagram of a liquid nitrogen adding device for a biological laboratory according to an embodiment of the utility model;

[0020] Figure 2 It is a top view of a protective cylinder of a liquid nitrogen adding device for a biological laboratory according to an embodiment of the utility model;

[0021] Figure 3 According to the embodiment of the utility model Figure 1 A magnified image of point A;

[0022] Figure 4 According to the embodiment of the utility model Figure 1 The enlarged view of point B;

[0023] Figure 5 It is a stereoscopic diagram of a clamping plate of a liquid nitrogen adding device for a biological laboratory according to an embodiment of the utility model.

[0024] In the figure:

[0025] 1. Base; 2. Rotating slide; 3. Hydraulic cylinder; 4. Rotating plate; 5. Rotating slip ring; 6. Gear ring; 7. Storage table; 8. Storage slot; 9. Lifting mounting plate; 10. Liquid inlet pipe; 11. Filling pump; 12. Liquid outlet pipe; 13. Solenoid valve; 14. Filling head; 15. Connecting plate; 16. Second servo motor; 17. Clamping plate; 18. Protective tube; 19. Bidirectional lead screw; 20. Lead screw sleeve; 21. Guide slide rod; 22. Guide slide sleeve; 23. Anti-slip rubber pad; 24. Mounting cavity; 25. Rotating shaft; 26. Gear; 27. First servo motor; 28. Temperature sensor; 29. ​​Buzzer alarm. DETAILED DESCRIPTION

[0026] To further illustrate each embodiment, the present invention provides drawings, which are part of the disclosure of the present invention and are mainly used to illustrate the embodiments. They can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, ordinary technicians in the field should be able to understand other possible implementation methods and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0027] According to an embodiment of the utility model, a liquid nitrogen adding device for a biological laboratory is provided.

[0028] The present invention is now further described in conjunction with the accompanying drawings and specific implementation methods. Figure 1-5As shown, a liquid nitrogen adding device for a biological laboratory according to an embodiment of the utility model comprises a base 1, a rotating plate 4 and a clamping plate 17, a hydraulic cylinder 3 is installed in the center of the top surface of the base 1, and the output end of the hydraulic cylinder 3 is connected to the lifting mounting plate 9, and a protective cylinder 18 is fixedly installed on one side of the bottom surface of the lifting mounting plate 9, a bidirectional lead screw 19 is installed on one side of the inner cavity of the protective cylinder 18, and one end of the bidirectional lead screw 19 is connected to the output end of the second servo motor 16, a guide slide bar 21 is fixedly installed on the other side of the inner cavity of the protective cylinder 18, the inner cavity of the protective cylinder 18 is symmetrically provided with a clamping plate 17, and a connecting plate 15 is fixedly installed on the top surface of the clamping plate 17, a lead screw sleeve 20 is fixedly installed on one end of the connecting plate 15, and the lead screw sleeve 20 cooperates with the bidirectional lead screw 19, a guide slide sleeve 22 is fixedly installed on the other end of the connecting plate 15, and the guide A guide slide rod 21 is sleeved in the sliding sleeve 22, a rotating slide groove 2 is provided on the top surface of the base 1, a rotating slip ring 5 is fixedly installed on the bottom surface of the rotating plate, and the rotating slip ring 5 is embedded in the rotating slide groove 2, a mounting cavity 24 is provided in the base 1, and a first servo motor 27 is installed in the mounting cavity 24, and a rotating shaft 25 is connected to the output end of the first servo motor 27, a gear 26 is fixedly installed on the rotating shaft 25, a gear ring 6 is fixedly installed on the side wall of the rotating plate 4, and the gear ring 6 and the gear 26 are meshed with each other, a plurality of storage tables 7 are evenly fixedly installed on the top surface of the rotating plate 4, and a storage groove 8 is provided on the top surface of the storage table 7, which can automatically realize the alignment of the filling container and the filling head 14, and can automatically realize the limit fixation of the filling container when adding liquid, the operation is simple and convenient, the liquid nitrogen filling efficiency is improved, and the practicality is stronger.

[0029] In one embodiment, a filling pump 11 is fixedly installed on the top surface of the lifting installation plate 9, and one side of the filling pump 11 is connected to the liquid inlet pipe 10, and the other side of the filling pump 11 is connected to the liquid outlet pipe 12, the liquid outlet pipe 12 is located in the inner cavity of the protection tube 18 and is connected to a filling head 14, and a solenoid valve 13 is installed on the liquid outlet pipe 12, a temperature sensor 28 located in the inner cavity of the protection tube 18 is installed on the bottom surface of the lifting installation plate 9, and a buzzer alarm 29 is fixedly installed on the top surface of the lifting installation plate 9, which plays a role in that when the liquid nitrogen leaks during the liquid nitrogen filling process, the low-temperature liquid nitrogen will also be in the protection tube 18. 8 inner cavity, it is not easy to spread outward quickly. The bottom surface of the lifting installation plate 9 is installed with a temperature sensor 28 located in the inner cavity of the protection tube 18. When the temperature sensor 28 detects that the temperature in the protection tube 18 drops rapidly, it can be known that a leakage has occurred during the liquid nitrogen filling process, and the signal can be fed back to the control panel. At this time, the control panel can stop the filling pump 11, and at the same time close the solenoid valve 13 installed on the liquid outlet pipe 12, and start the installed buzzer alarm 29 to alarm, so as to remind the user to deal with it in time, prevent the risk of accidents and reduce the loss of liquid nitrogen, which is more practical.

[0030] In one embodiment, a control panel is installed on the side wall of the base 1, and the control panel is electrically connected to the hydraulic cylinder 3, the first servo motor 27, the second servo motor 16, the temperature sensor 28, the filling pump 11, the solenoid valve 13 and the buzzer alarm 29. The control circuit of the control panel can be realized through simple programming by technicians in this field. It belongs to the common knowledge in this field and is only used without modification. Therefore, the control method and circuit connection will not be described in detail.

[0031] In one embodiment, the central axes of the base 1 , the hydraulic cylinder 3 , the rotating plate 4 , the rotating slide groove 2 and the rotating slip ring 5 are on the same straight line.

[0032] In one embodiment, the two clamping plates 17 are arc-shaped plates, and anti-slip rubber pads 23 are symmetrically fixedly installed on opposite sides of the two clamping plates 17 , thereby improving the clamping stability of the two clamping plates 17 .

[0033] In one embodiment, the inner diameter of the protection tube 18 is greater than the diameter of the placement table 7 .

[0034] In one embodiment, the rotating plate 4 is an annular plate.

[0035] Working principle: The utility model is provided with a rotating plate 4, a protective tube 18 and a clamping plate 17, a hydraulic cylinder 3 is installed in the center of the top surface of the base 1, and the output end of the hydraulic cylinder 3 is connected to the lifting installation plate 9, a filling pump 11 is installed on the lifting installation plate 9, and one side of the filling pump 11 is connected to the liquid inlet pipe 10, and the other side of the filling pump 11 is connected to the liquid outlet pipe 12, one end of the liquid outlet pipe 12 is connected to the filling head 14, and the other end is convenient, a rotating slide 2 is provided on the top surface of the base 1, and the rotating slip ring 5 fixedly installed on the bottom surface of the rotating plate 4 is embedded in the rotating slide 2, and a plurality of storage tables 7 are evenly fixedly installed on the top surface of the rotating plate 4, and a storage groove 8 is provided on the top surface of the storage table 7. When in use, the user can place the filling The container is placed in the storage slot 8, and then the first servo motor 27 installed in the installation cavity 24 is started through the control panel to drive the rotating shaft 25 to rotate. Because the gear 26 fixedly installed on the rotating shaft 25 is meshed with the gear ring 6 fixedly installed on the side wall of the rotating plate 4, the first servo motor 27 can drive the rotating plate 4 together with the storage platform 7 and the filling container to rotate. When the filling container rotates to below the filling head 14, the control panel can start the hydraulic cylinder 3 to drive the lifting installation plate 9 to descend. The bottom surface of the lifting installation plate 9 is fixedly installed with a protective tube 18, and as the lifting installation plate 9 descends, it can be sleeved on the outside of the storage platform 7. The inner cavity of the protective tube 18 is symmetrically provided with clamping plates 17, and the top of the clamping plate 17 is fixedly installed with a connecting plate 15, and the connecting plate A screw sleeve 20 is fixedly installed at one end of 15, a bidirectional screw 19 is installed on one side of the inner cavity of the protective tube 18, and one end of the bidirectional screw 19 is connected to the output end of the second servo motor 16, and the bidirectional screw 19 cooperates with the screw sleeve 20. On the other hand, a guide slide sleeve 22 fixedly installed at the other end of the connecting plate 15 is sleeved with a guide slide rod 21, so as the rotation of the bidirectional screw 19 can drive the two clamping plates 17 to move relative to each other, until the two clamping plates 17 push the filling container placed in the storage groove 8 to the center position of the protective tube 18, at this time, it can be ensured that the filling port of the filling container is aligned with the filling head 14. After loosening the two clamping plates 17, the hydraulic cylinder 3 drives the lifting mounting plate 9 together with the filling head 14 to continue to descend, so that the filling head 14 The liquid nitrogen filling device is connected to the filling port of the filling container, and the filling container is stably clamped by two clamping plates 17 equipped with anti-skid rubber pads 23, so that the liquid nitrogen filling and replenishing operation can be carried out. After the filling is completed, the hydraulic cylinder 3 drives the lifting and mounting plate 9 together with the protective tube 18 to reset, and the rotating plate 4 drives the storage table 7 and the filling container to continue to rotate, so that the user can take down the filling container after the filling. Such a cycle can form a continuous operation, so as to quickly add liquid to the batch of liquid nitrogen bottles to be replenished in the biological laboratory. Therefore, a liquid nitrogen filling device for a biological laboratory can automatically realize the alignment of the filling container and the filling head 14, and can automatically realize the limit fixation of the filling container during the filling. The operation is simple and convenient, the liquid nitrogen filling efficiency is improved, and the practicality is stronger.In addition, the utility model is provided with a protective tube 18, a temperature sensor 28 and a buzzer alarm 29. As mentioned above, when the liquid nitrogen filling operation is performed, the filling container and the filling head 14 are located in the inner cavity of the protective tube 18, thereby effectively preventing the user from accidentally touching the inner cavity and causing frostbite. When the liquid nitrogen leaks during the liquid nitrogen filling process, the low-temperature liquid nitrogen will also be in the inner cavity of the protective tube 18, and it is not easy to diffuse outward quickly. The bottom surface of the lifting and mounting plate 9 is installed with a temperature sensor 28 located in the inner cavity of the protective tube 18. When the temperature sensor 28 detects that the temperature in the protective tube 18 drops rapidly, it can be known that a leakage has occurred during the liquid nitrogen filling process, and the signal can be fed back to the control panel. At this time, the control panel can stop the filling pump 11, and at the same time close the solenoid valve 13 installed on the liquid outlet pipe 12, and start the installed buzzer alarm 29 to alarm, so as to remind the user to handle it in time, prevent the risk of accidents, and reduce the loss of liquid nitrogen, so as to ensure the safety of the use of the liquid nitrogen filling device in the biological laboratory, and it is more practical.

[0036] In the present utility model, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "screw-on" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the utility model according to the specific circumstances.

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A liquid nitrogen adding device for a biological laboratory, comprising a base (1), a rotating plate (4) and a clamping plate (17), characterized in that: A hydraulic cylinder (3) is installed in the center of the top surface of the base (1), and the output end of the hydraulic cylinder (3) is connected to a lifting installation plate (9), and a protective tube (18) is fixedly installed on one side of the bottom surface of the lifting installation plate (9), a bidirectional lead screw (19) is installed on one side of the inner cavity of the protective tube (18), and one end of the bidirectional lead screw (19) is connected to the output end of the second servo motor (16), and a guide slide bar (21) is fixedly installed on the other side of the inner cavity of the protective tube (18), a clamping plate (17) is symmetrically arranged in the inner cavity of the protective tube (18), and a connecting plate (15) is fixedly installed on the top surface of the clamping plate (17), one end of the connecting plate (15) is fixedly installed with a lead screw sleeve (20), and the lead screw sleeve (20) cooperates with the bidirectional lead screw (19), and the other end of the connecting plate (15) is fixedly installed with a guide slide bar (21). A sliding sleeve (22) is provided, and a guide sliding rod (21) is sleeved in the guide sliding sleeve (22); a rotating sliding groove (2) is provided on the top surface of the base (1); a rotating sliding ring (5) is fixedly installed on the bottom surface of the rotating plate, and the rotating sliding ring (5) is embedded in the rotating sliding groove (2); a mounting cavity (24) is provided in the base (1), and a first servo motor (27) is installed in the mounting cavity (24); a rotating shaft (25) is connected to the output end of the first servo motor (27); a gear (26) is fixedly installed on the rotating shaft (25); a gear ring (6) is fixedly installed on the side wall of the rotating plate (4), and the gear ring (6) and the gear (26) are meshed with each other; a plurality of storage tables (7) are evenly fixedly installed on the top surface of the rotating plate (4), and a storage groove (8) is provided on the top surface of the storage table (7).

2. A liquid nitrogen adding device for biological laboratories according to claim 1, characterized in that: A filling pump (11) is fixedly mounted on the top surface of the lifting installation plate (9), and one side of the filling pump (11) is connected to a liquid inlet pipe (10), and the other side of the filling pump (11) is connected to a liquid outlet pipe (12), one end of the liquid outlet pipe (12) located in the inner cavity of the protection tube (18) is connected to a filling head (14), and a solenoid valve (13) is installed on the liquid outlet pipe (12), a temperature sensor (28) located in the inner cavity of the protection tube (18) is installed on the bottom surface of the lifting installation plate (9), and a buzzer alarm (29) is fixedly mounted on the top surface of the lifting installation plate (9).

3. A liquid nitrogen adding device for biological laboratory according to claim 1, characterized in that: A control panel is installed on the side wall of the base (1), and the control panel is electrically connected to the hydraulic cylinder (3), the first servo motor (27), the second servo motor (16), the temperature sensor (28), the filling pump (11), the solenoid valve (13) and the buzzer alarm (29).

4. A liquid nitrogen adding device for biological laboratories according to claim 1, characterized in that: The central axes of the base (1), the hydraulic cylinder (3), the rotating plate (4), the rotating slide groove (2) and the rotating slip ring (5) are located on the same straight line.

5. The liquid nitrogen adding device for biological laboratory according to claim 1, characterized in that: The two clamping plates (17) are arc-shaped plates, and anti-skid rubber pads (23) are symmetrically fixedly installed on opposite sides of the two clamping plates (17).

6. A liquid nitrogen adding device for biological laboratory according to claim 1, characterized in that: The inner diameter of the protective tube (18) is greater than the diameter of the storage platform (7).

7. The liquid nitrogen adding device for biological laboratory according to claim 1, characterized in that: The rotating plate (4) is an annular plate.

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