Centrifugal automatic liquid taking device

Abstract

The utility model relates to a centrifugal automatic liquid taking equipment. The utility model aims at solving the problem that the algae enrichment is long in time, the operation is complicated, the sedimentation is easy to be disturbed, there is pollution risk and automatic accurate constant volume cannot be realized in the prior art. The system comprises: a centrifuge host, a centrifuge tube with a tube cover, and an automatic liquid discharge assembly. The tube cover is provided with a central through hole for butt joint of a liquid discharge pipe and a vent hole in which a one-way duckbill valve is embedded. The automatic liquid discharge assembly comprises: a siphon pipe module, a peristaltic pump for assisting siphon establishment, a non-contact photoelectric sensor and an intelligent control system. After centrifugation, the system is automatically vertically crimped and sealed, and adopts a "pump-assisted establishment + natural siphon" mode to gently discharge liquid; when the photoelectric sensor detects that the liquid level drops to a preset height, the control system immediately cuts off the flow path. The utility model realizes fully automatic operation, greatly shortens the enrichment time, and realizes zero disturbance, zero pollution and high-precision constant volume.

Description

Technical Field

[0001] This utility model relates to the field of sample pretreatment technology for environmental monitoring, and in particular to a fully automated centrifugation enrichment and precise volume determination device for algal samples in water bodies (such as surface water and ocean water). Background Technology

[0002] In environmental monitoring, especially in the monitoring of algae in water bodies (phytoplankton counting), since the concentration of algae in water samples is usually low, it is necessary to enrich (concentrate) the large volume of water samples collected. This is a key step in sample pretreatment.

[0003] Currently, the recommended method in existing standards (such as HJ1216-2021) is natural settling. This method involves allowing the water sample to stand (e.g., for 48 hours) until the algae settle to the bottom of the container by gravity, after which the supernatant is manually removed. This method has significant drawbacks: 1. Extremely long time consumption: The entire process takes more than 48 hours, which severely restricts the timeliness and efficiency of monitoring.

[0004] 2. Cumbersome operation and poor consistency: It relies on manual operation, the process is cumbersome, and the results of different operators are inconsistent.

[0005] To overcome the time-consuming nature of natural sedimentation, the industry commonly uses general-purpose centrifuges to accelerate sedimentation. However, after the centrifugation (solid-liquid separation) step, the subsequent "supernatant removal" and "volume adjustment" steps still heavily rely on manual labor, introducing new technical drawbacks: 1. Risk of secondary transfer and contamination: Samples may need to be transferred between centrifuge tubes and final containers, or there is a risk of cross-contamination when tools (such as pipettes) are used when aspirating the supernatant.

[0006] 2. Sample loss due to sediment disturbance: After centrifugation, algae settle at the bottom of the tube. When manually removing the supernatant by pouring or pipetting, the sediment at the bottom of the tube is easily disturbed, causing the algae to resuspend ("backmixing"), resulting in sample loss and affecting the accuracy of counting.

[0007] 3. Inability to accurately adjust volume: Manual operation makes it difficult to accurately control the final remaining liquid volume (e.g., adjusting to 5ml), resulting in inaccurate enrichment factor and poor consistency.

[0008] Therefore, existing algae enrichment technologies still have problems to be solved in terms of automation, standardization, enrichment efficiency, prevention of sedimentation disturbance, and precise volume determination. Utility Model Content

[0009] The purpose of this application is to address the aforementioned problems in the prior art by providing a fully automated centrifuge device that integrates centrifugation, automatic compression sealing, pump-assisted / natural siphon drainage, and photoelectric sensing for precise volume determination.

[0010] To achieve the above-mentioned objectives, this application adopts the following technical solution: an automatic centrifugal liquid extraction device comprising: Centrifuge tubes; The centrifuge main unit has a rotor for accommodating at least one centrifuge tube; A cap that can be sealed over the opening of a centrifuge tube, the cap having at least one drain outlet and one vent inlet. Automatic drainage assembly, including: The drain pipe is adapted to connect to the drain outlet after centrifugation. The drain pipe has an end that extends into the centrifuge tube. The pipe cap is also provided with a connecting pipe that connects to the end of the drain pipe. The end of the connecting pipe has a preset height corresponding to the target volume. A mating sealing assembly is used to form a seal at the mating point when the drain pipe and the pipe cap are mated. The liquid level detection unit, whose monitoring position corresponds to the preset height at the end of the drain pipe, is used to generate a trigger signal when the liquid level in the centrifuge tube drops to the preset height; A flow path control valve is installed on the flow path of the drain pipe; The intelligent control system is electrically connected to the centrifuge main unit, the liquid level detection unit, and the flow path control valve; The intelligent control system is used to control the automatic drain assembly to connect with the tube cap and open the flow path control valve to drain the supernatant after the centrifugation process is completed. The intelligent control system is also used to immediately close the flow path control valve upon receiving a trigger signal from the liquid level detection unit in order to achieve precise volume control.

[0011] Furthermore, the automatic drainage assembly is a siphon system, and the drainage pipe is a movable siphon pipe.

[0012] Furthermore, the siphon system further includes an auxiliary pump; the intelligent control system is used to control the auxiliary pump to run briefly at the beginning of the drainage phase to assist in establishing the siphon, and then stop the auxiliary pump, relying on natural siphon to complete the main drainage process.

[0013] Furthermore, a one-way valve is embedded in the vent on the tube cap. The one-way valve is used to allow outside air to enter the centrifuge tube to balance the pressure during drainage.

[0014] Furthermore, the liquid level detection unit is a non-contact photoelectric sensor, which is fixedly installed on the side of the centrifuge tube.

[0015] Furthermore, the mating sealing assembly uses a vertical downward pressing method to achieve a tight seal between the sealing end face of the top of the pipe cap and the drainage assembly.

[0016] Furthermore, the centrifuge tube is provided with a connecting pipe that connects to the drain pipe. The end of the connecting pipe has a U-shaped hook, and the lowest point of the hook is the preset height.

[0017] Furthermore, the drain pipe is integrated into the siphon module, which has a self-sealing connector. The self-sealing connector includes a compression spring and a silicone pad. In the unconnected state, the compression spring pushes the silicone pad to keep the flow path closed. When connected, the downward pressure of the connection sealing assembly opens the connector and establishes a liquid channel.

[0018] Furthermore, it also includes a positioning unit for controlling the rotor to rotate to a preset docking position after centrifugation, and the rotor of the centrifuge main unit is a horizontal rotor.

[0019] Furthermore, the mating sealing assembly includes a vertical press-fit sealing end face located at the opening of the centrifuge tube, and a sealing ring is embedded in the vertical press-fit sealing end face.

[0020] Compared with existing technologies, it has the following significant advantages: 1. Fully automated and highly efficient: It achieves a "one-click" fully automated operation from sample addition to final volume determination, without the need for manual intervention, and revolutionarily shortens the enrichment time from more than 48 hours in traditional methods to about 30 minutes.

[0021] 2. Zero transfer and zero contamination: The entire enrichment and volume adjustment process is completed in the same standard centrifuge tube, completely avoiding sample loss and cross-contamination risks caused by "secondary transfer" operations.

[0022] 3. Gentle and undisturbed: The innovative "pump-assisted establishment + natural siphon" drainage mechanism, combined with the one-way duckbill valve on the tube cap to automatically balance the air pressure, ensures a gentle and stable flow rate during the discharge of supernatant, minimizes disturbance to algae that have settled at the bottom of the tube, and ensures a high sample recovery rate.

[0023] 4. Precise volume control: The liquid level is monitored in real time by a non-contact infrared photoelectric sensor. When the liquid level drops to the preset 5ml mark, the closed-loop control of the system immediately cuts off the flow path, ensuring the volume control accuracy (e.g. ±0.2ml) and solving the problem of inaccurate manual volume control.

[0024] 5. High reliability and low cost: The automated architecture of "horizontal rotor + vertical pressure seal" is adopted, combined with self-sealing siphon joint, which simplifies the mechanical structure; at the same time, the core consumable is only a standard centrifuge tube, which greatly reduces the cost of using automated testing. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the equipment.

[0026] Figure 2 This is a cross-sectional view showing the docking state of the pipe cap and the siphon module.

[0027] Figure 3 This is a schematic diagram of the structure of the movable siphon tube inserted into the siphon guide groove of the centrifuge tube.

[0028] Figure 4 This is a cross-sectional view of the top of the centrifuge tube and siphon tube.

[0029] Figure 5 This is a schematic diagram of the overall structure; Figure 6 yes Figure 2 Enlarged view of A in the middle; Figure 7 This is a schematic diagram of a self-sealing connector.

[0030] In the diagram: 1. Self-sealing connector; 2. Remaining liquid state after siphoning; 3. Peristaltic pump; 4. Solenoid valve; 5. Drain pipe; 6. Moving siphon tube; 7. Centrifuge tube cover; 8. Centrifuge tube base; 9. Duckbill check valve; 10. Siphon opening bracket; 11. Guide groove; 12. O-ring; 13. Flow guide hole; 14. Lifting module; 15. Centrifuge tube; 16. Centrifuge tube mounting bracket; 17. Laser sensor detection hole; 18. Laser sensor detection positioning hole; 19. Integrated vent; 20. Rigid siphon tube; 21. 5ml graduation line; 22. Remaining solution after siphoning; 23. Compression spring; 24. Silicone pad; 25. Centrifuge cover; 27. Centrifuge rotating bracket; 28. Laser sensor; 29. ​​Centrifuge base; 30. Bottom cover plate; 31. Centrifuge intelligent control system; 32. Drain outlet; 33. Centrifuge rotation device fixing rod; 34. Centrifuge rotation motor. Detailed Implementation

[0031] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0032] Those skilled in the art should understand that, in the disclosure of this application, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limitations on this application.

[0033] This embodiment provides a fully automated centrifugation system for the rapid enrichment of algae.

[0034] Please see Figure 5 The diagram shows the overall structure of the present invention. The system includes: a centrifuge main unit, a rotor (specifically a centrifuge tube mounting bracket 16) installed inside the centrifuge main unit, at least one centrifuge tube 15 (consisting of a centrifuge tube base 8 and a centrifuge tube cover 7), and an automatic draining assembly.

[0035] The centrifuge main unit includes a centrifugal rotary motor 34, a centrifuge intelligent control system 31, and a liquid level detection unit (specifically a laser sensor 28) located on the side wall. Other conventional components include a centrifuge base 29, a bottom cover plate 30, a drain outlet 32, and a centrifugal rotary device fixing rod 33. The specific structural settings and installation relationships are all conventional operations and will not be described in detail here. The protection point of this utility model is not the structure of the centrifuge main unit, but the structure of the part that cooperates with the centrifuge tube 15, because the centrifuge used in this utility model is a modified centrifuge platform based on a standard horizontal rotor.

[0036] Automatic drainage assembly (e.g.) Figure 1 , Figure 5 As shown, the centrifuge is located on the upper part of the main unit and includes a lifting module 14 (an existing linear motor structure or linear module that can achieve vertical lifting with a repeatability of ±0.1mm), a siphon peristaltic pump 3 (i.e., an auxiliary pump), a solenoid valve 4 (i.e., a flow path control valve), and one or more movable siphon tubes 6 (i.e., drain pipes). Figure 1 The state of the remaining liquid after siphoning can be seen as 2.

[0037] Please refer to the following: Figure 2 , Figure 4 as well as Figure 6This is one of the core components of this utility model: the tube cap (shown as centrifuge tube cap 7). The centrifuge tube cap 7 seals the opening of the centrifuge tube base 8. It has a central through-hole at its upper part, with a guide cone (guide groove 11) for guiding the insertion of the movable siphon tube 6. This through-hole is the drain outlet, and its bottom has a guide hole 13. A vertical pressing sealing end face is provided in the top area of ​​the centrifuge tube cap 7 (below the guide groove 11), and an O-ring 12 (sealing ring) is embedded therein to form a reliable seal during connection. The centrifuge tube cap 7 also has an integrated vent 19, which integrates a one-way duckbill valve 9, serving as the vent inlet. This one-way duckbill valve 9 allows outside air to enter the tube during draining to balance the internal pressure and prevent negative pressure.

[0038] Please refer to the following: Figure 1 , Figure 2 , Figure 4 The core component of the automatic drainage assembly is the siphon module. This module consists of a movable siphon tube 6 and a rigid siphon tube 20 (i.e., a connecting pipe) located at the bottom of the centrifuge tube cap 7. This rigid siphon tube 20 connects to the movable siphon tube 6 via a guide hole 13 after the movable siphon tube 6 is inserted into the guide groove 11. The rigid siphon tube 20 is preferably made of 316 stainless steel. The end of the rigid siphon tube 20 is precisely calibrated into a U-shaped hook, with the lowest point of the hook precisely corresponding to the 5ml graduation line 21 inside the centrifuge tube. This 5ml graduation line 21 is the "preset height" in this embodiment; however, it can also be other preset heights, such as 2, 3, or 4ml, depending on the requirements.

[0039] Please see Figure 1 and Figure 5 The upper end of the movable siphon pipe 6 is connected in sequence to the siphon peristaltic pump 3 (or other type of peristaltic pump) and the solenoid valve 4 through a pipeline, and finally connected to the drain outlet 32.

[0040] Please see Figure 2 , Figure 6 as well as Figure 7In this embodiment, the mobile siphon module also integrates a self-sealing connector 1. This connector contains a compression spring 23, a silicone pad 24, and an opening bracket 35 that supports the silicone pad 24. A through hole is located at the center of the opening. In the unconnected state, the compression spring 23 pushes the silicone pad 24 to block the through hole inside the mobile siphon 6, keeping the flow path of the mobile siphon 6 sealed. When the system is connected, the lifting module 14 presses down vertically, and the siphon opening bracket 10 inside the centrifuge tube 15 pushes the silicone pad 24 upwards (the siphon opening bracket 10 pushes the silicone pad 24, which acts as a "plug," upwards, disengaging it from the "valve seat," thus creating an annular channel; a certain gap can be seen between the silicone pad 24 and the inner wall of the mobile siphon 6, and the outer diameter of the siphon opening bracket 10 is smaller than the diameter of the through hole in the aforementioned opening bracket 35), compressing the compression spring 23 and opening the flow path.

[0041] Please see Figure 3 and Figure 5 In this embodiment, the rotor is a horizontal rotor (centrifuge tube mounting bracket 16). The centrifuge tube mounting bracket 16 is provided with a laser sensor detection and positioning hole 18 (i.e., positioning unit), which is used to cooperate with the sensor on the centrifuge host (i.e., liquid level detection unit or laser sensor 28) to ensure that after centrifugation, the rotor can stop at a precise docking position, so that the moving siphon tube 6 can be aligned with the tube cap below.

[0042] Please see Figure 3 and Figure 5 The liquid level detection unit (laser sensor 28, such as a photoelectric sensor) is fixedly installed on the side wall of the centrifuge main unit. Its optical path (through the laser sensor detection hole 17) is precisely aligned with the 5ml mark 21 of the centrifuge tube 15 when it is in a static docking state.

[0043] The centrifuge intelligent control system 31 (i.e., intelligent control system, which can be PLC or single-chip microcomputer system, belongs to conventional structure and is not an improvement of computer program or method) is the brain of this system. It is electrically connected to the centrifugal rotary motor 34, lifting module 14, siphon peristaltic pump 3, laser sensor 28 and solenoid valve 4.

[0044] The working process (action process) of this embodiment is as follows: Taking enriching a 100ml water sample into 5ml as an example: 1. Sample Addition and Centrifugation: The user injects 100ml of water sample into the centrifuge tube base 8, tightens the tube cap (centrifuge tube top cover 7), and places it in the centrifuge tube mounting bracket 16. The user closes the centrifuge top cover 25 and starts the centrifugation program built into the centrifuge unit (this is existing technology and not an improvement on a computer program or method). The intelligent control system 31 controls the centrifuge rotary motor 34 to start, driving the horizontal rotor (centrifuge tube mounting bracket 16) to centrifuge at 1200rpm for 15 minutes.

[0045] 2. Automatic Docking: After centrifugation, the centrifugal rotary motor 34 stops. The positioning unit (laser sensor detecting positioning hole 18) ensures the rotor is accurately positioned at the docking position. Subsequently, the lifting module 14 starts, driving the automatic drainage assembly to press down vertically. The moving siphon tube 6 is inserted through the guide cone (guide groove 11) on the tube cover. During the pressing process, the O-ring 12 is compressed, forming an external seal; at the same time, the siphon opening bracket 10 pushes open the internal silicone pad 24, opening the drainage path.

[0046] 3. Pump-assisted siphon establishment: The intelligent control system 31 opens the solenoid valve 4 and controls the siphon peristaltic pump 3 to run in reverse at a low speed (e.g., 25 rpm) for 5 seconds. This action uses pump force to quickly draw the supernatant in the centrifuge tube 15 through the U-shaped bend, establishing an effective siphon level difference.

[0047] 4. Gentle Siphon Drainage: After the siphon is established, the intelligent control system 31 immediately stops the siphon peristaltic pump 3. At this time, the solenoid valve 4 remains open, and the liquid flows gently and steadily to the drain outlet, ultimately being discharged from the drain port 32 of the centrifuge main unit, relying on the natural siphon pressure difference established by the system. During this process, the one-way duckbill valve 9 on the tube cover automatically opens to replenish air, ensuring smooth drainage without disturbing the algae sediment at the bottom of the tube.

[0048] 5. Precise Volume Adjustment and Cut-off: The supernatant level continues to drop. A laser sensor 28 (liquid level detection unit) fixed to the side wall monitors the position of the 5ml mark 21 in real time. When the liquid level drops to the 5ml mark, the optical path state changes, and the laser sensor 28 immediately generates a trigger signal and sends it to the intelligent control system 31.

[0049] 6. Upon receiving the trigger signal, the intelligent control system 31 immediately (e.g., within 0.3 seconds) controls the solenoid valve 4 to close, instantly cutting off the siphon flow path and completing precise volume control.

[0050] 7. System Reset: The lifting module 14 rises, causing the automatic drainage assembly to reset. The movable siphon tube 6 disengages from the tube cover, and its internal compression spring 23 pushes the silicone gasket 24 to automatically reset and seal, preventing residual liquid in the pipeline from dripping or flowing back.

[0051] 8. Completed: The system indicates that the operation is complete. The user opens the centrifuge lid 25 and removes the centrifuge tubes 15 that have undergone enrichment and precise volume adjustment.

[0052] In summary, this utility model, through the above-described structure, achieves full automation from centrifugation, automatic docking, gentle drainage to precise volume determination, solving the problems of long processing time, easy disturbance, easy contamination, and inaccurate volume determination in existing technologies.

[0053] The parts not described in detail in this application are prior art, and therefore are not described in detail in this application.

[0054] It is understood that the term "a" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element can be one, while in another embodiment, the number of the element can be multiple, and the term "a" should not be understood as a limitation on the number.

[0055] Although this document uses a significant amount of technical terminology, the possibility of using other terms is not excluded. These terms are used merely to facilitate the description and explanation of the nature of this application; interpreting them as any additional limitation would be contrary to the spirit of this application.

[0056] This application is not limited to the above-described preferred embodiments. Anyone can derive other products in various forms under the guidance of this application. However, regardless of any changes made to their shape or structure, any technical solution that is the same as or similar to that of this application falls within the protection scope of this application.

Claims

1. An automatic centrifugal liquid extraction device, characterized in that, include: Centrifuge tubes; The centrifuge main unit has a rotor for accommodating at least one of the centrifuge tubes; A cap that can be sealed over the opening of the centrifuge tube, the cap having at least one drain outlet and one vent inlet; Automatic drainage assembly, including: A drain pipe is adapted to connect to the drain outlet after centrifugation, the drain pipe having an end that extends into the centrifuge tube; wherein, the pipe cap is also provided with a connecting pipe that connects to the end of the drain pipe, the end of the connecting pipe having a preset height corresponding to the target fixed volume. A mating sealing assembly is used to form a seal at the mating point when the drain pipe and the pipe cap are mated; The liquid level detection unit, whose monitoring position corresponds to a preset height at the end of the drain pipe, is used to generate a trigger signal when the liquid level in the centrifuge tube drops to the preset height; A flow path control valve is installed on the flow path of the drain pipe; An intelligent control system is electrically connected to the centrifuge main unit, the liquid level detection unit, and the flow path control valve; The intelligent control system is used to control the automatic drain assembly to connect with the tube cap and open the flow path control valve to drain the supernatant after the centrifugation process is completed. The intelligent control system is also used to immediately control the flow path control valve to close when it receives a trigger signal from the liquid level detection unit, so as to achieve precise volume control.

2. The automatic centrifugal liquid extraction device according to claim 1, characterized in that, The automatic drainage assembly is a siphon system, and the drainage pipe is a movable siphon pipe.

3. The automatic centrifugal liquid extraction device according to claim 2, characterized in that, The siphon system further includes an auxiliary pump; the intelligent control system is used to control the auxiliary pump to run briefly to assist in establishing a siphon at the beginning of the drainage phase, and then stop the auxiliary pump to complete the main drainage process by relying on natural siphon.

4. The automatic centrifugal liquid extraction device according to claim 1, characterized in that, The vent on the tube cap is fitted with a one-way valve, which allows outside air to enter the centrifuge tube to balance the pressure during drainage.

5. The automatic centrifugal liquid extraction device according to claim 1, characterized in that, The liquid level detection unit is a non-contact photoelectric sensor, which is fixedly installed on the side of the centrifuge tube.

6. The automatic centrifugal liquid extraction device according to claim 1, characterized in that, The mating sealing assembly achieves a tight seal between the sealing end face of the top of the pipe cap and the drainage assembly by pressing it down vertically.

7. The automatic centrifugal liquid extraction device according to claim 1, characterized in that, The end of the connecting pipe has a U-shaped hook, and the lowest point of the hook is the preset height.

8. An automatic centrifugal liquid extraction device according to any one of claims 1-7, characterized in that, The drain pipe is integrated into the siphon module, which has a self-sealing connector. The self-sealing connector includes a compression spring and a silicone pad. In the unconnected state, the compression spring pushes the silicone pad to keep the flow path closed. When connected, the downward pressure of the connection sealing assembly opens the connector and establishes a liquid channel.

9. An automatic centrifugal liquid extraction device according to any one of claims 1-7, characterized in that, It also includes a positioning unit for controlling the rotor to rotate to a preset docking position after centrifugation, and the rotor of the centrifuge main unit is a horizontal rotor.

10. An automatic centrifugal liquid extraction device according to any one of claims 1-7, characterized in that, The docking sealing assembly includes a vertical press-fit sealing end face located at the opening of the centrifuge tube, and a sealing ring is embedded in the vertical press-fit sealing end face.

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