Valve device for preventing liquid backflow of manual pipette

Abstract

The utility model relates to the technical field of pipette backflow prevention, in particular to a manual pipette liquid backflow prevention valve device, which comprises a first pipe body, a second pipe body, a third pipe body and a fourth pipe body, according to the utility model, the diaphragm can be pushed to descend by the air pressure generated by the operation of the pipette, and then the second piston is pushed to descend by the support plate and the second rod body, so that the air below the second piston in the negative pressure pipe is discharged through the one-way valve; if liquid rapidly flows back due to misoperation and other reasons, the liquid firstly enters the first pipe body and enters the annular shell through the porous structure at the bottom of the annular shell, the liquid is adsorbed through the sponge in the annular shell so that the liquid can be prevented from penetrating through the annular shell, and if the liquid is too much and penetrates through the annular shell, the liquid is prevented from flowing out of the annular shell. And liquid entering the position above the negative pressure pipe is buffered through negative pressure.

Description

Technical Field

[0001] This utility model relates to the field of anti-backflow technology for pipettes, specifically a liquid backflow prevention valve device for manual pipettes. Background Technology

[0002] Pipettes are commonly used in laboratories to transfer small or trace amounts of liquid. Their basic principle is that the negative pressure generated inside the pipette acts on the tip, creating a negative pressure state inside the tip. The negative pressure is used to draw the sample liquid, and then the positive pressure generated inside the pipette releases the sample liquid from the tip. During this process, due to operational errors or other reasons, sample liquid from inside the tip may enter the pipette, causing contamination. To address this, a manual pipette liquid backflow prevention valve device is proposed.

[0003] In the prior art, most pipettes have a large chamber between the pipette tip and the pipette tip to prevent liquid backflow. However, this design has a small upper limit for preventing backflow, and it is still impossible to prevent liquid samples from entering the pipette when the liquid enters at a fast speed. Utility Model Content

[0004] The purpose of this invention is to provide a liquid backflow prevention valve device for manual pipettes to solve the problems mentioned in the background art.

[0005] The technical solution of this utility model is: a manual pipette liquid backflow prevention valve device, comprising:

[0006] The first tube body has a threaded protrusion at its top.

[0007] A connecting assembly, which is connected to a first tube body via a threaded protrusion;

[0008] A diaphragm is fixed to the top of the inner wall of the first tube.

[0009] Multiple fixing components, all of which are fixed to the inner wall of the first tube;

[0010] An annular shell, which is fixed by multiple fixing components and a first tube, has a porous structure at the top and bottom, and is filled with sponge.

[0011] A negative pressure pipe, wherein the negative pressure pipe is disposed within an annular shell;

[0012] The second piston is slidably disposed inside the negative pressure tube;

[0013] A transmission assembly, wherein the transmission assembly is connected to the second piston, and the transmission assembly is connected to the diaphragm;

[0014] A one-way valve is installed through the bottom of the negative pressure pipe.

[0015] Preferably, the fixing component includes:

[0016] A plate, which is fixed to the inner wall of the first tube;

[0017] The first magnet is fixed to the bottom of the plate.

[0018] The second magnet is fixed to the top of the annular shell.

[0019] Preferred options also include:

[0020] Multiple connecting rods, all of which are fixed to the bottom of the annular shell;

[0021] A connecting ring is fixed to multiple connecting rods.

[0022] Preferably, the transmission assembly includes:

[0023] The second rod is fixed to the top of the second piston;

[0024] A support plate is fixed to the top of the second piston, and the support plate and the diaphragm are fixed together.

[0025] Preferred options also include:

[0026] Two multi-stage telescopic rods, both of which are fixed to the support plate;

[0027] Two plugs are fixed to the telescopic ends of the two multi-stage telescopic rods, respectively.

[0028] Preferred options also include:

[0029] Two hoses, both of which pass through the top of the negative pressure tube and both of which pass through the bottom of the second piston, and each hose is adapted to a plug.

[0030] Preferred options also include:

[0031] A spring is fixed to the bottom inner wall of the negative pressure tube, and the spring and the second piston are also fixed.

[0032] Preferably, the connection component includes:

[0033] The second tube body is fixed to the first tube body by a threaded protrusion;

[0034] A first piston, which is slidably disposed within a second tube;

[0035] The first rod is fixed to the bottom of the first piston.

[0036] Preferred options also include:

[0037] A support plate is fixed to the bottom of the first rod, and the support plate abuts against the diaphragm.

[0038] This utility model provides an improved liquid backflow prevention valve device for manual pipettes, which has the following improvements and advantages compared with the prior art:

[0039] This invention, through its connecting components, diaphragm, annular shell, negative pressure tube, and transmission components, enables the air pressure generated during pipette operation to push the diaphragm downward. This, in turn, pushes the second piston downward via the support plate and the second rod, allowing the gas below the second piston in the negative pressure tube to be discharged through a one-way valve, thus maintaining a negative pressure state in the negative pressure tube. If liquid rapidly flows back due to operational errors, the liquid first enters the first tube and then enters the annular shell through the porous structure at the bottom of the annular shell. The sponge inside the annular shell absorbs the liquid, preventing it from passing through the annular shell. If there is too much liquid and it passes through the annular shell, the negative pressure then buffers the liquid entering the upper part of the negative pressure tube. Attached Figure Description

[0040] The present invention will be further explained below with reference to the accompanying drawings and embodiments:

[0041] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;

[0042] Figure 2 This is a schematic cross-sectional view of the second tube body of this utility model;

[0043] Figure 3 This is a schematic diagram of the cross-sectional structure of the first tube body of this utility model;

[0044] Figure 4 This is a schematic diagram of the annular shell and connecting rod structure of this utility model;

[0045] Figure 5 This is a cross-sectional structural diagram of the negative pressure pipe of this utility model.

[0046] Explanation of reference numerals in the attached figures:

[0047] 1. First tube body; 2. Second tube body; 3. First piston; 4. Connecting ring; 5. First rod body; 6. Support plate; 7. Diaphragm; 8. Threaded protrusion; 9. Second rod body; 10. Hoses; 11. Plug; 12. Multi-stage telescopic rod; 13. Plate body; 14. First magnet; 15. Second magnet; 16. Annular shell; 17. Connecting rod; 18. Support plate; 19. Second piston; 20. Spring; 21. One-way valve; 22. Negative pressure pipe. Detailed Implementation

[0048] The present invention will now be described in detail, and the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0049] This utility model provides an improved liquid backflow prevention valve device for manual pipettes. The technical solution of this utility model is as follows:

[0050] like Figures 1-5 As shown, a manual pipette backflow prevention valve device includes:

[0051] First tube body 1, the top of the first tube body 1 is provided with threaded protrusion 8;

[0052] A connecting assembly is connected to the first tube body 1 via a threaded protrusion 8;

[0053] Diaphragm 7, diaphragm 7 is fixed to the top of the inner wall of the first tube 1;

[0054] Multiple fixing components are fixed to the inner wall of the first tube body 1;

[0055] An annular shell 16 is fixed to the first tube 1 by multiple fixing components. The top and bottom of the annular shell 16 are porous structures, and the annular shell 16 is filled with sponge.

[0056] Negative pressure pipe 22 is installed inside the annular shell 16;

[0057] The second piston 19 is slidably disposed inside the negative pressure tube 22;

[0058] The transmission assembly is connected to the second piston 19, and the transmission assembly is also connected to the diaphragm 7.

[0059] One-way valve 21 is installed through the bottom of negative pressure pipe 22.

[0060] The gas pressure generated by the pipette operation pushes the first piston 3 down. During this process, the first rod 5 and the support plate 6 push the diaphragm 7 down, which in turn pushes the second piston 19 down through the support plate 18 and the second rod 9, so that the gas in the negative pressure tube 22 below the second piston 19 is discharged through the one-way valve 21, so that the negative pressure tube 22 is in a negative pressure state.

[0061] If the liquid flows back rapidly due to operational errors or other reasons, the liquid first enters the first tube 1 and then enters the annular shell 16 through the porous structure at the bottom of the annular shell 16. The liquid is then absorbed by the sponge inside the annular shell 16 to prevent the liquid from passing through the annular shell 16.

[0062] If there is too much liquid, and it passes through the annular shell 16, the liquid entering the negative pressure pipe 22 is buffered by negative pressure.

[0063] Furthermore, the fixing components include:

[0064] Plate 13 is fixed to the inner wall of the first tube 1;

[0065] The first magnet 14 is fixed to the bottom of the plate 13;

[0066] The second magnet 15 is fixed to the top of the annular shell 16.

[0067] Furthermore, it also includes:

[0068] Multiple connecting rods 17 are fixed to the bottom of the annular shell 16;

[0069] Connecting ring 4, and multiple connecting rods 17 are fixed together.

[0070] After the annular shell 16 is contaminated by the sample, it can be removed by connecting ring 4 and connecting rod 17. Then, a new annular shell 16 can be installed in the first tube 1 by the action of plate 13, first magnet 14 and second magnet 15, and then the work can be resumed.

[0071] Furthermore, the transmission components include:

[0072] The second rod 9 is fixed to the top of the second piston 19;

[0073] Support plate 18 is fixed to the top of the second piston 19, and support plate 18 and diaphragm 7 are fixed together.

[0074] Furthermore, it also includes:

[0075] Two multi-stage telescopic rods 12 are fixed to the support plate 18;

[0076] Two plugs 11 are fixed to the telescopic ends of the two multi-stage telescopic rods 12 respectively.

[0077] Furthermore, it also includes:

[0078] Two hoses 10 are connected to the top of the negative pressure pipe 22 and the bottom of the second piston 19. The two hoses 10 are respectively matched with the two plugs 11.

[0079] When the diaphragm 7 is in normal condition, the diaphragm 7 drives the support plate 18 to the normal position. At this time, the plug 11 on the multi-stage telescopic rod 12 is still inside the hose 10, that is, the hose 10 is in a sealed state.

[0080] When the diaphragm 7 is abnormally reset, the support plate 18 is in a higher position. At this time, the plug 11 is moved away from the hose 10 by the multi-stage telescopic rod 12.

[0081] Furthermore, it also includes:

[0082] Spring 20 is fixed to the bottom inner wall of negative pressure tube 22, and spring 20 is also fixed to the second piston 19.

[0083] When the second piston 19 descends, it compresses the spring 20. Through the action of the spring 20, the second piston 19 is pushed upward, giving the second piston 19 an upward tendency to move. This causes the negative pressure tube 22 below the second piston 19 to be in a negative pressure state.

[0084] Furthermore, the connection components include:

[0085] The second tube body 2 is fixed to the first tube body 1 by the threaded protrusion 8;

[0086] The first piston 3 is slidably disposed inside the second tube 2;

[0087] The first rod 5 is fixed to the bottom of the first piston 3.

[0088] Furthermore, it also includes:

[0089] Support plate 6 is fixed to the bottom of the first rod 5, and support plate 6 and diaphragm 7 are in contact.

[0090] Specifically, the working principle is as follows: When in use, first fix the second tube 2 onto the pipette, then fix the first tube 1 and the second tube 2 together through the threaded protrusion 8, and then fix the pipette tip onto the first tube 1.

[0091] During sampling, the air pressure generated by the pipette pushes the first piston 3 down. In this process, the first rod 5 and the support plate 6 push the diaphragm 7 down, which in turn pushes the second piston 19 down through the support plate 18 and the second rod 9. This allows the gas in the negative pressure tube 22 below the second piston 19 to be discharged through the one-way valve 21. At the same time, the spring 20 is compressed. Through the action of the spring 20, the second piston 19 is pushed upward, giving the second piston 19 an upward tendency. This keeps the area in the negative pressure tube 22 below the second piston 19 in a negative pressure state.

[0092] After the gas is discharged, the gas inside the pipette tip is also discharged. Then the sample is drawn up. A negative pressure is generated inside the pipette, which causes the first piston 3 to reset. At the same time, the gas pressure in the first tube 1 below the diaphragm 7 is reduced, which in turn reduces the gas pressure in the pipette tip, so as to achieve liquid aspiration.

[0093] If the liquid flows back rapidly due to operational errors or other reasons, the liquid first enters the first tube 1 and then enters the annular shell 16 through the porous structure at the bottom of the annular shell 16. The liquid is then absorbed by the sponge inside the annular shell 16 to prevent the liquid from passing through the annular shell 16.

[0094] After the annular shell 16 is contaminated by the sample, the annular shell 16 can be removed by the connecting ring 4 and the connecting rod 17. Then, the new annular shell 16 can be installed in the first tube 1 by the action of the plate 13, the first magnet 14 and the second magnet 15, and the work can be carried out again.

[0095] If the negative pressure in the pipette is too high, too much liquid will enter the annular shell 16. The liquid will pass through the porous structure above the annular shell 16 and enter the upper part of the annular shell 16. At the same time, the diaphragm 7 is also highly reset. Through the action of the support plate 18 and the multi-stage telescopic rod 12, the two plugs 11 are moved away from the hose 10. This allows the liquid entering the upper part of the annular shell 16 to enter the lower part of the second piston 19 through the hose 10, thereby achieving liquid buffering. Finally, the diaphragm 7 blocks the liquid to prevent it from entering the second tube 2, thus ensuring the cleanliness of the inside of the pipette.

Claims

1. A liquid backflow prevention valve device for a manual pipette, characterized by The utility model relates to a kind of negative pressure device, including: First pipe body (1), the first pipe body (1) top is provided with threaded boss (8); Connecting assembly, the connecting assembly is connected by threaded boss (8) and first pipe body (1); Diaphragm (7), the diaphragm (7) is fixed in first pipe body (1) inner wall top; Multiple fixed assemblies, multiple the fixed assemblies are fixed on the inner wall of first pipe body (1); Annular shell (16), the annular shell (16) is fixed by multiple fixed assemblies and first pipe body (1), the top and bottom of the annular shell (16) are porous structure, the annular shell (16) is filled with sponge; Negative pressure pipe (22), the negative pressure pipe (22) is arranged in annular shell (16); Second piston (19), the second piston (19) is slidably arranged in negative pressure pipe (22); Transmission assembly, the transmission assembly is connected with second piston (19), and transmission assembly and diaphragm (7) are connected; One-way valve (21), the one-way valve (21) is arranged through the bottom of negative pressure pipe (22).

2. A liquid backflow prevention valve device for a manual pipette according to claim 1, characterized in that The fixed assembly includes: Plate body (13), the plate body (13) is fixed on the inner wall of first pipe body (1); First magnet (14), the first magnet (14) is fixed in plate body (13) bottom; Second magnet (15), the second magnet (15) is fixed in annular shell (16) top.

3. A liquid backflow prevention valve device for a manual pipette according to claim 1, characterized in that Further including: Multiple connecting rods (17), multiple the connecting rods (17) are fixed in annular shell (16) bottom; Connecting ring (4), the connecting ring (4) is fixed with multiple connecting rods (17).

4. The liquid backflow prevention valve device for a manual pipette according to claim 1, characterized by The transmission assembly includes: Second rod body (9), the second rod body (9) is fixed in second piston (19) top; Supporting plate (18), the supporting plate (18) is fixed in second piston (19) top, and supporting plate (18) and diaphragm (7) are fixed.

5. A liquid backflow prevention valve device for a manual pipette according to claim 4, characterized in that Further including: Two multi-stage telescopic rods (12), two the multi-stage telescopic rods (12) are fixed with supporting plate (18); Two plugs (11), two the plugs (11) are respectively fixed in the telescopic end of two multi-stage telescopic rods (12).

6. A liquid backflow prevention valve device for a manual pipette according to claim 5, characterized in that Further including: Two hoses (10), two the hoses (10) are respectively through the top of negative pressure pipe (22), two the hoses (10) are respectively through the bottom of second piston (19), and two hoses (10) are respectively matched with two plugs (11).

7. A liquid backflow prevention valve device for a manual pipette according to claim 1, wherein Further including: Spring (20), the spring (20) is fixed on the inner wall of the bottom of negative pressure pipe (22), and spring (20) and second piston (19) are fixed.

8. A liquid backflow prevention valve device for a manual pipette according to claim 1, characterized in that The connecting assembly includes: Second pipe body (2), the second pipe body (2) is fixed by threaded boss (8) and first pipe body (1); First piston (3), the first piston (3) is slidably arranged in second pipe body (2); First rod body (5), the first rod body (5) is fixed in first piston (3) bottom.

9. A liquid backflow prevention valve device for a manual pipette according to claim 8, characterized in that Further including: Supporting plate (6), the supporting plate (6) is fixed in first rod body (5) bottom, and supporting plate (6) and diaphragm (7) are in contact.

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