Filter element suction head structure of pipettor

Abstract

The utility model discloses a pipettor filter element suction head structure which comprises a suction head shell and a backflow prevention mechanism, and a filter element is arranged at the bottom end of the inner wall of the suction head shell; the backflow prevention mechanism comprises a first piston head, a connecting frame, a first telescopic column, a connecting base, a second piston head and a limiting assembly, the first piston head is located at the lower end of the interior of the suction head shell, the connecting frame is arranged on the lower side of the first piston head, the connecting base is arranged on the bottom wall of the connecting frame through the telescopic end of the first telescopic column, and the second piston head is arranged on the upper side of the connecting base; according to the pipettor filter element suction head structure, through the transmission element, by means of the air pressure difference and the elastic force of the spring, the suction opening part can be automatically blocked after the pipettor filter element suction head extracts liquid, the suction opening part can be automatically blocked, and the suction opening part can be automatically blocked after the pipettor filter element suction head extracts the liquid. The phenomenon that liquid flows back and is discharged from the suction head of the filter element is avoided, the accurate quantity of the pipettor is ensured, and the accuracy of subsequent experimental results is improved.

Description

Technical Field

[0001] This utility model relates to the field of pipette technology, specifically to a pipette filter tip structure. Background Technology

[0002] A pipette, also called a pipette tip, is a measuring tool used to transfer liquid from one container to another within a certain volume range. During use, the pipette tip and filter cartridge are used to pump and displace liquid. In existing technology: [Authorization Publication No. CN 218281802] U's patent discloses a filter cartridge pipette tip for use in a pipette, including a pipette tip body with a filter cartridge installed inside. Different sized filter cartridges are fixedly positioned at different locations within the pipette tip body. The pipette tip body consists of a connector and a suction tube, with an oxidation mechanism inside the suction tube to improve accuracy. The filter cartridge is doped with a water-sensitive color-changing material made of polyethylene or tetrafluoroethylene. By incorporating the oxidation mechanism inside the suction tube, issues such as mixing or residue buildup can be effectively prevented when releasing liquid after aspiration, thus improving experimental accuracy. However, during the process of drawing liquid using an external pipette, some liquid may remain inside the pipette tip body. This residual liquid may flow back along the pipette tip body wall to the nozzle and be discharged, leading to inaccurate pipetting volume and affecting subsequent experimental results. Therefore, we propose a pipette tip filter cartridge structure. Utility Model Content

[0003] The technical problem to be solved by this utility model is to overcome the existing defects and provide a pipette filter tip structure. This device, through a transmission element, utilizes air pressure difference and spring force to automatically seal the pipette tip after the pipette filter tip draws liquid, preventing liquid backflow from the pipette tip and ensuring accurate pipette volume. This improves the accuracy of subsequent experimental results and can effectively solve the problems in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a pipette filter tip structure, including a tip shell, a filter element provided at the bottom of the inner wall of the tip shell, and an anti-backflow mechanism;

[0005] Anti-backflow mechanism: It includes piston head one, connecting frame, telescopic column one, connecting seat, piston head two, and limiting component. Piston head one is located at the lower end of the inner part of the pipette tip housing. A connecting frame is provided on the lower side of piston head one. A connecting seat is provided on the bottom wall of the connecting frame through the telescopic end of telescopic column one. Piston head two is provided on the upper side of the connecting seat. Piston head two is installed in conjunction with the conical through-slot opened in the middle of piston head one. A limiting component is provided between piston head one and pipette tip housing. This device, through a transmission element, utilizes air pressure difference and spring force to automatically seal the pipette tip after the pipette tip draws liquid, preventing liquid backflow from the pipette tip, ensuring accurate pipette volume, and improving the accuracy of subsequent experimental results.

[0006] Furthermore, the upper outer side of the suction head shell is provided with six evenly distributed reinforcing ribs, which improve the strength of the device itself and thus increase its service life.

[0007] Furthermore, a rubber plug is inserted into the bottom of the pipette tip housing. When the pipette tip is not in use, the bottom of the pipette tip is sealed to prevent external dust and other impurities from entering from the bottom of the pipette tip.

[0008] Furthermore, the anti-backflow mechanism also includes a spring, which is movably sleeved on the outer end of the telescopic column. One end of the spring is fixedly connected to the connecting frame, and the other end of the spring is fixedly connected to the piston head, so that the piston head inside the pipette filter tip can automatically reset after the position of the piston head moves.

[0009] Furthermore, the anti-backflow mechanism also includes a rubber sealing ring one and a rubber sealing ring two. The rubber sealing ring one is disposed on the outer side of the piston head two, and the rubber sealing ring two is disposed on the outer side of the piston head one, thereby improving the sealing effect of the piston head two and the piston head one inside the pipette filter tip.

[0010] Furthermore, the limiting component includes an annular frame, two telescopic columns, two springs, and an annular seat. The annular frame is located at the lower end of the inside of the pipette tip housing. An annular seat is provided in the annular groove opened at the upper end of the piston head. Four evenly distributed telescopic columns and two springs are provided between the annular seat and the annular frame. Each of the two springs is movably sleeved with the outer end of the adjacent telescopic column to limit the position of the piston head in the pipette tip.

[0011] Furthermore, the inner wall of the pipette tip housing is coated with a KNM17 high-molecular ceramic polymer coating to improve the corrosion resistance of the inner wall of the pipette tip.

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows: This pipette filter tip structure has the following advantages:

[0013] When using a pipette filter tip, the system utilizes the pressure difference and spring force of the piston head, connecting bracket, telescopic column, spring, connecting seat, piston head, rubber sealing ring, rubber sealing ring, and limiting assembly to automatically seal the nozzle after the pipette filter tip draws liquid. This prevents liquid backflow from the filter tip, ensuring accurate pipetting and improving the precision of subsequent experimental results. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model;

[0015] Figure 2 This is a cross-sectional structural diagram of the present invention;

[0016] Figure 3 This is an enlarged structural diagram of point A in this utility model.

[0017] In the diagram: 1. Suction head shell, 2. Reinforcing rib, 3. Rubber plug, 4. Filter element, 5. Anti-backflow mechanism, 51. Piston head one, 52. Connecting frame, 53. Telescopic column one, 54. Spring one, 55. Connecting seat, 56. Piston head two, 57. Rubber sealing ring one, 58. Rubber sealing ring two, 59. Limiting assembly, 591. Ring frame, 592. Telescopic column two, 593. Spring two, 594. Ring seat. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] Please see Figure 1-3 This embodiment provides a technical solution: a pipette filter tip structure, including a tip shell 1, a filter element 4 at the bottom of the inner wall of the tip shell 1, six evenly distributed reinforcing ribs 2 at the upper outer side of the tip shell 1, a rubber plug 3 inserted into the bottom of the tip shell 1, and a KNM17 polymer ceramic coating on the inner wall of the tip shell 1. When using the pipette filter tip, the tip shell 1 is connected to an external pipette, and then the rubber plug 3 is pulled out from the lower end of the tip shell 1, thereby removing the bottom sealing protection of the tip shell 1. The reinforcing ribs 2 improve the structural strength of the upper curved part of the device, thereby improving its service life. The KNM17 polymer ceramic coating on the inner wall of the tip shell 1 has extremely high isolation and extremely low permeability, preventing the penetration of acid, oxygen, and water vapor, making the inner wall of the tip shell 1 highly corrosion resistant. It also includes an anti-backflow mechanism 5.

[0020] Anti-backflow mechanism 5: It includes piston head 51, connecting frame 52, telescopic column 53, connecting seat 55, piston head 56, and limiting component 59. Piston head 51 is located at the lower end of the inside of suction head shell 1. Connecting frame 52 is provided on the lower side of piston head 51. Connecting seat 55 is provided on the bottom wall of connecting frame 52 through the telescopic end of telescopic column 53. Piston head 56 is provided on the upper side of connecting seat 55. Piston head 56 is fitted with a tapered through groove in the middle of piston head 51. Limiting component 59 is provided between piston head 51 and suction head shell 1. Anti-backflow mechanism 5 also includes spring 54. Spring 54 is movably sleeved on the outer end of telescopic column 53. One end of spring 54 is fixedly connected to connecting frame 52, and the other end of spring 54 is connected to piston head 56. The second piston head 56 is fixedly connected. The anti-backflow mechanism 5 also includes a rubber sealing ring 57 and a rubber sealing ring 58. The rubber sealing ring 57 is located on the outer side of the piston head 56, and the rubber sealing ring 58 is located on the outer side of the piston head 51. The limiting component 59 includes an annular frame 591, a telescopic column 592, a spring 593, and an annular seat 594. The annular frame 591 is located at the lower end of the inner part of the suction head housing 1. The annular seat 594 is located in the annular groove at the upper end of the piston head 51. Four evenly distributed telescopic columns 592 and springs 593 are provided between the annular seat 594 and the annular frame 591. The springs 593 are all movably sleeved with the outer ends of the adjacent telescopic columns 592. When the operator uses a pipette to aspirate liquid, at this time... The bottom of the pipette tip housing 1 contacts the surface of the liquid being sucked. The suction force applied by the pipette to the inside of the pipette tip housing 1 gradually increases, and the upward thrust exerted on the piston head 51 by the air pressure gradually increases. When this suction force increases to a certain extent, the piston head 51 overcomes the compressive force of the spring 593 and the downward pressure exerted on it by the gas above the piston head 51, thus moving upward. The telescopic end of the telescopic column 592 and the spring 593 retract. As the piston head 51 moves upward, it gradually separates from the bottom conical surface of the pipette tip housing 1, thereby releasing the sealing restriction on the bottom of the pipette tip housing 1. Subsequently, the liquid passes through the bottom suction port of the pipette tip housing 1 and is filtered through the filter element 4. The filtered liquid passes through the outer side of the piston head 51 and the inner wall of the pipette tip housing 1. The gap formed between the two parts moves upward into the external pipette. After the pipette finishes drawing liquid, the air pressure above the piston head 51 returns to normal. The spring 593's contraction and reset force causes the piston head 51 to move downward, automatically sealing the bottom of the pipette tip housing 1 and preventing backflow of liquid. When liquid in the pipette is discharged through the filter tip, it enters the pipette tip housing 1 along with the pipette. When the pressure exerted by the liquid in the pipette tip housing 1 on the piston head 56 reaches a certain level, the piston head 56 overcomes the compression force of the spring 54 and moves downward, releasing the seal of the piston head 56 on the conical groove. This allows the liquid to drain through the gap between the piston head 56 and the conical groove. When not in use...The compression and reset force of spring 54 causes piston head 56 to reset and re-seal the conical groove. Rubber sealing ring 57 reduces the contact gap between piston head 51 and pipette tip housing 1, improving the sealing effect. Rubber sealing ring 58 reduces the sealing gap between piston head 56 and the conical groove, further improving the sealing effect. This device, through transmission elements and utilizing air pressure difference and spring force, automatically seals the pipette tip after liquid is drawn from the filter cartridge, preventing backflow and ensuring accurate pipette volume, thus improving the precision of subsequent experimental results.

[0021] The working principle of the pipette filter tip structure provided by this utility model is as follows: When using the pipette filter tip, the tip housing 1 is connected to the external pipette. Then, the rubber stopper 3 is pulled out from the lower end of the tip housing 1, thereby releasing the bottom sealing protection of the tip housing 1. Then, the operator uses the pipette to perform liquid aspiration. At this time, the bottom of the tip housing 1 is in contact with the surface of the aspirated liquid. The liquid aspiration force applied by the pipette to the tip housing 1 gradually increases, and the upward thrust exerted on the piston head 51 by the air pressure gradually increases. When the aspiration force increases to a certain extent, the piston head 51 overcomes the spring 593. The compression force of the spring and the downward pressure exerted on the piston head 51 by the gas above it cause it to move upward. The telescopic end of the telescopic column 592 and the spring 593 retract. As the piston head 51 moves upward, it gradually separates from the bottom conical surface of the pipette head housing 1, thereby releasing the sealing restriction on the bottom of the pipette head housing 1. The liquid then passes through the bottom suction port of the pipette head housing 1 and is filtered through the filter element 4. The filtered liquid moves upward through the gap formed between the outer side of the piston head 51 and the inner wall of the pipette head housing 1 and enters the external pipette. When the pipette finishes drawing liquid, the gas pressure above the piston head 51 returns to normal, and the spring 593 retracts. The reset spring force causes piston head 51 to move downwards and reset, automatically sealing the bottom of pipette tip housing 1 to prevent backflow of liquid inside. When liquid in the pipette tip is discharged through the filter cartridge, it enters pipette tip housing 1 along with the pipette. When the pressure exerted by the liquid in pipette tip housing 1 on piston head 56 reaches a certain level, piston head 56 overcomes the compression force of spring 54 and moves downwards, releasing the blockage of the conical groove by piston head 56, allowing liquid to drain through the gap between piston head 56 and the conical groove. When not in use, the compression reset spring force of spring 54 causes piston head 56 to reset again. The conical through groove is sealed, and the contact gap between the piston head 51 and the suction head shell 1 is reduced by the rubber sealing ring 57, thereby improving the sealing effect between the two. The sealing gap between the piston head 56 and the conical through groove is reduced by the rubber sealing ring 58, thereby improving the sealing effect between the two. The structural strength of the upper curved part of the device is improved by the reinforcing rib 2, thereby improving its service life. The inner wall of the suction head shell 1 is coated with KNM17 high molecular ceramic polymer. KNM17 high molecular ceramic polymer has extremely high isolation and extremely low permeability, preventing the penetration of acid, oxygen and water vapor, so that the inner wall of the suction head shell 1 has strong corrosion resistance.

[0022] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the content of this utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A pipette tip structure with filter cartridge, comprising a tip housing (1), wherein a filter cartridge (4) is provided at the bottom end of the inner wall of the tip housing (1), characterized in that: It also includes an anti-backflow mechanism (5); Anti-backflow mechanism (5): It includes piston head one (51), connecting frame (52), telescopic column one (53), connecting seat (55), piston head two (56) and limiting component (59). The piston head one (51) is located at the lower end of the inside of the suction head shell (1). The connecting frame (52) is provided on the lower side of the piston head one (51). The bottom wall of the connecting frame (52) is provided with the connecting seat (55) through the telescopic end of the telescopic column one (53). The piston head two (56) is provided on the upper side of the connecting seat (55). The piston head two (56) is installed in conjunction with the tapered through groove opened in the middle of the piston head one (51). The limiting component (59) is provided between the piston head one (51) and the suction head shell (1).

2. The pipette filter tip structure according to claim 1, characterized in that: The upper outer side of the suction head shell (1) is provided with six evenly distributed reinforcing ribs (2).

3. The pipette filter tip structure according to claim 1, characterized in that: A rubber plug (3) is inserted into the bottom of the suction head housing (1).

4. The pipette filter tip structure according to claim 1, characterized in that: The anti-backflow mechanism (5) also includes a spring (54), which is movably sleeved on the outer end of the telescopic column (53). One end of the spring (54) is fixedly connected to the connecting frame (52), and the other end of the spring (54) is fixedly connected to the piston head (56).

5. The pipette filter tip structure according to claim 1, characterized in that: The anti-backflow mechanism (5) also includes a rubber sealing ring one (57) and a rubber sealing ring two (58). The rubber sealing ring one (57) is disposed on the outer side of the piston head two (56), and the rubber sealing ring two (58) is disposed on the outer side of the piston head one (51).

6. The pipette filter tip structure according to claim 1, characterized in that: The limiting component (59) includes an annular frame (591), telescopic post two (592), spring two (593) and an annular seat (594). The annular frame (591) is located at the lower end of the inside of the suction head shell (1). The annular seat (594) is provided in the annular groove opened at the upper end of the piston head one (51). Four evenly distributed telescopic posts two (592) and spring two (593) are provided between the annular seat (594) and the annular frame (591). The spring two (593) is movably sleeved with the outer end of the adjacent telescopic post two (592).

7. The pipette filter tip structure according to claim 1, characterized in that: The inner wall of the suction head shell (1) is coated with KNM17 polymer ceramic coating.

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