Sealing device and pipettor

Abstract

The sealing device comprises a first sealing assembly and a second sealing assembly, the first sealing assembly is arranged at the end, away from a gun head, of an inner cavity, the first sealing assembly comprises a sealing lantern ring, a first pressing plate and a first sealing ring, the sealing lantern ring is embedded in the inner cavity, and the first pressing plate is arranged on the first sealing ring. The first pressing plate is partially embedded in the inner cavity and abuts against the sealing lantern ring, the sealing lantern ring is in interference fit with the outer diameter of the piston rod, and the first sealing ring is arranged on the outer wall of the sealing lantern ring in a sleeving mode so as to apply radial pressing force to the sealing lantern ring; the second sealing assembly is arranged at the joint of the cylinder body and the gun head and comprises a second sealing ring, a second pressing plate and a push plate, the gun head is sleeved with the second sealing ring, the second pressing plate is embedded in the cylinder body and presses the gun head, and the push plate is connected to the cylinder body so as to press the second pressing plate. According to the technical scheme, the sealing effect and durability of the pipettor are improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to pipettor technical field, especially a sealing device and pipettor. BACKGROUND

[0002] As a widely used liquid handling tool in the laboratory, pipettor has the function of accurate suction, transfer and release of liquid, and is widely used in biomedical, chemical analysis, pharmaceutical, environmental monitoring and other fields. With the improvement of laboratory automation, the accuracy, efficiency, durability and multifunctionality of pipettor are also increasing.

[0003] At present, the sealing device of pipettor usually relies on sealing ring or other rubber materials, although it can ensure the basic sealing of liquid, but due to long time liquid operation and high frequency use, the sealing element is easy to wear, which leads to sealing failure, thereby affecting the accuracy and reliability of pipettor. UTILITY MODEL CONTENT

[0004] The main purpose of the utility model is to provide a sealing device and pipettor, which aims to improve the sealing effect and durability of pipettor.

[0005] In order to achieve the above purpose, the utility model adopts the following technical scheme.

[0006] Firstly, the utility model provides a sealing device applied to pipettor, which comprises a cylinder body, a piston rod and a gun head, an inner cavity is arranged in the cylinder body, the piston rod is slidingly connected to the inner cavity, an inner hole is arranged in the gun head, the gun head is connected to the cylinder body, the inner hole is communicated with the inner cavity, and the sealing device comprises:

[0007] A first sealing assembly is arranged at one end of the inner cavity away from the gun head, the first sealing assembly comprises a sealing sleeve ring, a first pressing plate and a first sealing ring, the sealing sleeve ring is embedded in the inner cavity, part of the first pressing plate is embedded in the inner cavity and abuts against the sealing sleeve ring, the sealing sleeve ring is in interference fit with the outer diameter of the piston rod, and the first sealing ring is sleeved on the outer wall of the sealing sleeve ring to apply radial compression force to the sealing sleeve ring; and

[0008] A second sealing assembly is arranged at the connection between the cylinder body and the gun head, the second sealing assembly comprises a second sealing ring and a second pressing plate, the second sealing ring is sleeved on the gun head, the second pressing plate is embedded in the cylinder body and presses the gun head, and the push plate is connected to the cylinder body.

[0009] In a possible implementation, the sealing sleeve ring comprises a sliding part and a ring pressing part, the ring pressing part is in clearance fit with the piston rod, the sliding part is in interference fit with the piston rod, and the first sealing ring is arranged on the outer wall of the sliding part.

[0010] In a possible implementation, the sealing sleeve ring is made of polyoxymethylene, polyamide or polytetrafluoroethylene.

[0011] The piston rod is made of ceramic.

[0012] In a possible implementation, the wall thickness of the sliding part is 0.3-0.5 mm.

[0013] In a possible implementation, the inner cavity is provided with a first groove, a second groove and a third groove, the sliding part is arranged in the first groove, the first sealing ring is arranged in the second groove, and the ring pressing part and part of the first pressing plate are arranged in the third groove.

[0014] In a possible implementation, the connection between the cylinder and the gun head is provided with a fourth groove, a fifth groove and a sixth groove, the gun head comprises a first step and a second step, the second sealing ring is arranged on the first step and arranged in the fourth groove, the second step is arranged in the fifth groove, and the second pressing plate is pressed against the second step and arranged in the sixth groove.

[0015] In a possible implementation, the connection between the cylinder and the gun head is further provided with a push plate.

[0016] In a second aspect, the utility model further provides a pipette, which comprises a pipette base plate, a screw rod driving part, a sliding block, a cylinder, a piston rod, a gun head and the sealing device as described in the first aspect or any possible implementation of the first aspect, the pipette base plate is provided with a guide rail, the sliding block is slidingly connected to the guide rail and connected to the piston rod, and the screw rod driving part is drivingly connected to the sliding block to drive the sliding block to move the piston rod.

[0017] The utility model discloses technical scheme is through adopting the first sealing assembly and second sealing assembly setting, the first sealing assembly sets up at the one end of inner chamber away from the gun head, and the first sealing assembly includes sealing sleeve ring, first pressure plate and first sealing ring, and the sealing sleeve ring is embedded in the inner chamber, and the part of first pressure plate is embedded in the inner chamber, and abuts to sealing sleeve ring, and the sealing sleeve ring is in external diameter interference fit with the piston rod, and the first sealing ring is nested in the outer wall of sealing sleeve ring, to the sealing sleeve ring radial pressure tight force is added, and the second sealing assembly sets up at the connecting place of cylinder body and gun head, and the second sealing assembly includes second sealing ring, second pressure plate and push plate, and the second sealing ring is nested in the gun head, and the second pressure plate is embedded in the cylinder body, and the push plate is connected to the cylinder body, to the second pressure plate is pressed tightly, the sealing sleeve ring of the application is in external diameter interference fit with the piston rod tightly, to ensure that liquid does not leak through the gap when the piston rod slides. However, the friction between the piston rod and the sealing sleeve ring needs to be overcome by proper radial compression to ensure the sealing effect in long-term use. The first sealing ring is nested on the outer wall of the sealing sleeve ring, which strengthens the sealing between the sealing sleeve ring and the inner cavity of the cylinder by applying radial compression. The elasticity of the sealing ring allows it to maintain close contact during piston rod movement, preventing gas or liquid leakage. Compared with traditional sealing devices, the wear of single sealing elements (such as O-rings) is reduced, improving the reliability and durability of the seal. The first sealing ring provides continuous sealing compression during piston rod movement by closely contacting the outer wall of the sealing sleeve ring, ensuring that the sealing sleeve ring is always in a stable sealing state and will not fail due to long-term use. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description are only some embodiments of the present utility model, and other drawings can be obtained according to the structures shown in these drawings without creative labor for those skilled in the art.

[0019] Figure 1 It is a structural schematic view of an embodiment of the sealing device of the present utility model.

[0020] Figure 2 It is a structural schematic view of an embodiment of the present utility model. Figure 1 It is a partial enlarged view of A in the middle.

[0021] Figure 3 It is a partial enlarged view of B in the middle. Figure 1

[0022] Figure 4 It is a structural schematic view of an embodiment of the present utility model.

[0023] BRIEF DESCRIPTION OF DRAWINGS ​

[0024] 100, sealing device; 10, first sealing assembly; 11, sealing sleeve ring; 111, sliding part; 112, ring pressing part; 12, first pressing plate; 13, first sealing ring; 20, second sealing assembly; 21, second sealing ring; 22, second pressing plate; 23, push plate; 30, cylinder; 301, inner cavity; 3011, first groove; 3012, second groove; 3013, third groove; 3014, fourth groove; 3015, fifth groove; 3016, sixth groove; 31, piston rod; 40, gun head; 401, inner hole; 402, first step; 403, second step; 200, pipette; 201, pipette base plate; 2011, guide rail; 202, screw driving part; 203, sliding block.

[0025] The realization, functional features and advantages of the utility model will be further explained in combination with embodiments and with reference to the drawings. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and advantages of the application more clear and explicit, the application will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the application and not to limit the application.

[0027] In the first aspect, in combination with the drawings, Figures 1 to 3 As shown in the drawings, the utility model discloses a kind of sealing devices 100, applied to pipette 200, the pipette 200 includes cylinder 30, piston rod 31 and gun head 40, the inner cavity 301 is provided in the cylinder 30, the piston rod 31 is slidably connected in the inner cavity 301, the inner hole 401 is provided in the gun head 40, the gun head 40 is connected to the cylinder 30, the inner hole 401 is communicated with the inner cavity 301, the sealing device 100 includes:

[0028] First sealing assembly 10, the first sealing assembly 10 is set to the end of the inner cavity 301 away from the gun head 40, the first sealing assembly 10 includes sealing sleeve ring 11, first pressing plate 12 and first sealing ring 13, the sealing sleeve ring 11 is embedded in the inner cavity 301, part of the first pressing plate 12 is embedded in the inner cavity 301, and abuts to the sealing sleeve ring 11, the sealing sleeve ring 11 is in interference fit with the outer diameter of the piston rod 31, the first sealing ring 13 is set on the outer wall of the sealing sleeve ring 11, to exert the radial pressing force to the sealing sleeve ring 11;And

[0029] A second sealing assembly 20 is provided at the joint of the cylinder 30 and the gun head 40, which includes a second sealing ring 21 and a second pressing plate 22. The second sealing ring 21 is sleeved on the gun head 40, and the second pressing plate 22 is embedded in the cylinder 30 and tightly presses the gun head 40.

[0030] In this embodiment, the cylinder 30 is used to provide a moving space and an inner cavity for accommodating the piston rod 31 and performing liquid suction and release. The piston rod 31 is in sliding connection with the inner cavity 301 of the cylinder 30 and participates in the process of liquid suction and release. The gun head 40 is connected to one end of the cylinder 30 and is connected to the inner cavity 301 of the cylinder 30 through the inner hole 401, which is used for transferring, sucking or releasing liquid. The first sealing assembly 10 is arranged at the end of the inner cavity 301 of the cylinder 30 away from the gun head 40, which is to ensure that no air leakage or liquid leakage occurs during the sliding process of the piston rod 31. The sealing sleeve ring 11 is the core part of the first sealing assembly 10, which is located in the inner cavity 301 of the cylinder 30 and is in interference fit with the outer diameter of the piston rod 31. The interference fit means that the inner diameter of the sealing sleeve ring 11 is slightly smaller than the outer diameter of the piston rod 31, which ensures that the sealing sleeve ring 11 can tightly surround the piston rod 31, avoiding liquid or gas leakage. The tight contact between the sealing sleeve ring 11 and the piston rod 31 ensures that the piston rod 31 maintains good sealing effect during the sliding process. The sealing sleeve ring 11 is usually made of wear-resistant materials (such as polyformaldehyde, polytetrafluoroethylene, etc.) to improve its durability and reduce friction, prolonging its service life. The first pressing plate 12 is partially embedded in the inner cavity 301 of the cylinder 30 and abuts against the sealing sleeve ring 11, which serves to press the sealing sleeve ring 11 tightly to ensure its stability and prevent displacement, and also strengthens the pressing force of the sealing sleeve ring 11 on the piston rod 31. The first pressing plate 12 is connected with the cylinder 30 by screws or other fixing devices during installation, ensuring that the sealing sleeve ring 11 maintains sealing contact with the piston rod 31 throughout the entire operation process. The cooperation between the first pressing plate 12 and the sealing sleeve ring 11 ensures that the pressure between the sealing sleeve ring 11 and the piston rod 31 is always maintained within a suitable range, avoiding sealing failure caused by uneven or unstable pressure. The first sealing ring 13 is sleeved on the outer wall of the sealing sleeve ring 11, which mainly serves to exert radial pressing force on the sealing sleeve ring 11, further enhancing the sealing effect. The first sealing ring 13 is usually made of high-elasticity, wear-resistant and high-temperature-resistant materials (such as rubber or polyurethane). It provides sealing performance between the outer wall of the sealing sleeve ring 11 and the inner cavity 301 of the cylinder 30, avoiding gas or liquid leakage. The design of the first sealing ring 13 ensures that the sealing sleeve ring 11 is always pressed tightly during the sliding process of the piston rod 31, thereby preventing any air or liquid leakage.

[0031] The second sealing assembly 20 is located at the joint of the cylinder 30 and the gun head 40, mainly used to ensure the sealing of the joint of the gun head 40 and the cylinder 30, to avoid liquid leakage outside the gun head 40. The second sealing ring 21 is sleeved on the gun head 40, to ensure the air tightness between the gun head 40 and the cylinder 30. The second pressing plate 22 is embedded in the inner cavity 301 of the cylinder 30 and presses the gun head 40, to further enhance the pressing effect of the second sealing ring 21 and prevent leakage.

[0032] The sealing sleeve 11 is tightly connected with the outer diameter of the piston rod 31 through interference fit, to ensure that the liquid will not leak through the gap when the piston rod 31 slides. However, the friction between the piston rod 31 and the sealing sleeve 11 needs to be overcome by appropriate radial compression, to ensure the sealing effect in long-term use. The first sealing ring 13 is sleeved on the outer wall of the sealing sleeve 11, to strengthen the sealing between the sealing sleeve 11 and the inner cavity 301 of the cylinder 30 by applying radial compression force. The elasticity of the sealing ring enables it to maintain close contact during the movement of the piston rod 31, to prevent gas or liquid leakage. Compared with the traditional sealing device, the wear of a single sealing member (such as an O-shaped sealing ring) is reduced, and the reliability and durability of the sealing are improved. The first sealing ring 13 can provide continuous sealing compression during the movement of the piston rod 31 through close contact with the outer wall of the sealing sleeve 11, to ensure that the sealing sleeve 11 is always in a stable sealing state and will not fail due to long-term use.

[0033] In combination with reference Figure 2 As shown, in one possible implementation, the sealing sleeve 11 includes a sliding part 111 and a ring pressing part 112, the ring pressing part 112 is clearance fit with the piston rod 31, the sliding part 111 is interference fit with the piston rod 31, and the first sealing ring 13 is sleeved on the outer wall of the sliding part 111.

[0034] In this embodiment, the sliding portion 111 and the ring pressing portion 112 can be integrally formed, and the sliding portion 111 is located on the inner side of the sealing sleeve ring 11 and is in interference fit with the outer diameter of the piston rod 31, that is, the inner diameter of the sliding portion 111 is slightly smaller than the outer diameter of the piston rod 31, so as to ensure that the sliding portion 111 and the piston rod 31 can maintain close contact. The sliding portion 111 is the contact surface between the sealing piston rod 31 and the inner cavity 301 of the cylinder 30, and the interference fit of the sliding portion 111 ensures that no air or liquid leaks outside the cylinder 30 when the piston rod 31 slides, thereby ensuring the sealing of the pipette 200. The sliding portion 111 is usually made of wear-resistant and corrosion-resistant materials (such as polytetrafluoroethylene, polyformaldehyde, etc.), so as to reduce the friction between the sliding portion 111 and the piston rod 31 and prolong the service life. The ring pressing portion 112 is located on the outer side of the sealing sleeve ring 11 and is in close fit with the design of the inner cavity 301 of the cylinder 30, and is usually in clearance fit, which allows the ring pressing portion 112 to maintain a certain space between the inner cavity 301 of the cylinder 30 during installation, so that it can be elastically deformed when subjected to pressure. The main function of the ring pressing portion 112 is to help the sealing sleeve ring 11 to be stably installed in the inner cavity 301 of the cylinder 30 through the contact with the inner cavity 301 of the cylinder 30, and to provide stability for the sealing sleeve ring 11 through its elastic properties. The ring pressing portion 112 also presses the sealing sleeve ring 11 through external pressure (such as the pressing force from the first pressing plate 12), thereby enhancing the sealing effect.

[0035] In a possible implementation, the material of the sealing sleeve ring 11 is polyformaldehyde, polyamide or polytetrafluoroethylene.

[0036] The material of the piston rod 31 is ceramic.

[0037] In the present embodiment, polyoxymethylene is a high-strength, wear-resistant engineering plastic widely used in applications requiring high mechanical strength and low friction coefficient. Polyoxymethylene has excellent wear resistance, low friction coefficient, good rigidity, and chemical resistance, thus effectively reducing the friction between the sliding parts 111, prolonging the service life of the sealing collar 11. The sealing collar 11 made of polyoxymethylene material can maintain low wear under high-frequency movement of the piston rod 31, and due to its good self-lubricating property, it reduces the heat generated by friction, further improving the sealing performance. Polyamide, commonly known as nylon, is an engineering plastic with excellent mechanical properties, particularly in terms of high strength, high toughness, and wear resistance. Polyamide material can provide good strength and wear resistance, especially under friction and compression load. The advantages of polyamide lie in its good dimensional stability and strong impact resistance, making it suitable for sealing applications that require certain mechanical impact and continuous sliding. Polytetrafluoroethylene is a highly corrosion-resistant polymer material with excellent chemical stability, low friction coefficient, excellent temperature resistance (good stability at high temperature), and low water absorption, avoiding the influence of environmental humidity on sealing effect. The sealing collar 11 made of polytetrafluoroethylene material can withstand more severe chemical environments and high-temperature working conditions, making it an ideal material for use in extreme conditions (such as high temperature and highly corrosive liquids). Ceramic is a material with extremely high hardness and wear resistance. The piston rod 31 made of ceramic material has strong wear resistance and chemical stability, making it particularly suitable for sealing devices 100 that require high wear resistance and do not deform over time.

[0038] In one possible implementation, the wall thickness of the sliding part 111 is 0.3mm-0.5mm.

[0039] In the present embodiment, if the wall thickness of the sliding part 111 is too thin, the material may be plastically deformed due to friction during long-term use, affecting the sealing effect. A too thin wall thickness may also reduce the strength of the sealing collar 11, causing the sliding part 111 to be easily damaged during use. In addition, a too thin wall thickness will result in insufficient elasticity of the sliding part 111, which cannot effectively maintain close contact with the piston rod 31, thus possibly causing gas or liquid leakage, affecting the use effect of the pipette 200.

[0040] If the wall thickness of the sliding part 111 is too thick, it will reduce the overall elasticity and flexibility of the sealing collar 11. A thicker wall thickness will increase the friction resistance, affecting the smooth movement of the piston rod 31, thus increasing energy consumption and reducing efficiency. A too thick wall thickness may increase the manufacturing cost and is not easy to accommodate in small-volume, precise pipette 200 devices, thus affecting the overall design and size of the device.

[0041] In the wall thickness range of 0.3mm-0.5mm, the sliding part 111 can have sufficient strength and durability while maintaining proper elasticity. This wall thickness range provides sufficient elasticity and toughness so that the sliding part 111 can maintain sealing during contact with the piston rod 31 and avoid air leakage. This wall thickness range can also ensure that the sealing sleeve ring 11 is not easily deformed or damaged during long-term use, while not increasing excessive frictional resistance, so that the piston rod 31 slides more smoothly, improving the operating efficiency of the pipette 200.

[0042] In one possible implementation, the position where the inner cavity 301 installs the first sealing assembly 10 is provided with a first groove 3011, a second groove 3012, and a third groove 3013, the sliding part 111 is accommodated in the first groove 3011, the first sealing ring 13 is accommodated in the second groove 3012, and the ring pressing part 112 and part of the first pressing plate 12 are accommodated in the third groove 3013.

[0043] With reference to Figure 2 As shown, in this embodiment, the first groove 3011 is used to accommodate the sliding part 111, which is part of the sealing sleeve ring 11 and is in sliding contact with the piston rod 31, responsible for maintaining good sealing and reducing friction. The function of the first groove 3011 is to accurately accommodate the sliding part 111, ensuring that the sliding part 111 can always be in close contact with the piston rod 31 during movement of the piston rod 31, thereby avoiding air leakage. The size and shape of the groove should match the outer shape of the sliding part 111 to ensure that the sliding part 111 can be stably embedded and will not be offset or misaligned when the piston rod 31 slides.

[0044] The second groove 3012 is used to accommodate the first sealing ring 13, which is sleeved on the outer wall of the sealing sleeve ring 11 and plays a role in enhancing sealing performance. The function of the second groove 3012 is to stably accommodate the first sealing ring 13 between the sealing sleeve ring 11 and the piston rod 31, and through reasonable groove design, it is ensured that the first sealing ring 13 can always be in a compressed state during work, avoiding gas or liquid leakage. The size and depth of the second groove 3012 also need to be accurately controlled to ensure that the sealing ring can be compressed without being extruded or failing.

[0045] The third groove 3013 is used to accommodate the ring pressing part 112 and the first pressing plate 12. The ring pressing part 112 is a part of the sealing sleeve ring 11, which applies radial pressing force to the sealing sleeve ring 11 through cooperation with the first pressing plate 12, ensuring the sealing effect between the sliding part 111 and the piston rod 31. The role of the third groove 3013 is to accommodate part of the ring pressing part 112 and the first pressing plate 12, so that it can be accurately fixed in the inner cavity 301. Through this design, the third groove 3013 ensures the cooperation accuracy between the ring pressing part 112 and the first pressing plate 12, so that the ring pressing part 112 can apply uniform pressing force to the first sealing ring 13 during work, ensuring that there is no leakage between the sealing sleeve ring 11 and the piston rod 31.

[0046] In combination with reference Figure 3 As shown in a possible implementation, a fourth groove 3014, a fifth groove 3015, and a sixth groove 3016 are arranged at the connection between the cylinder body 30 and the gun head 40. The gun head 40 includes a first step 402 and a second step 403. The second sealing ring 21 is sleeved on the first step 402 and accommodated in the fourth groove 3014. The second step 403 is accommodated in the fifth groove 3015. The second pressing plate 22 is pressed against the second step 403 and accommodated in the sixth groove 3016.

[0047] In this embodiment, the fourth groove 3014 is used to accommodate the second sealing ring 21. The role of the second sealing ring 21 is to prevent liquid or gas from leaking at the connection between the cylinder body 30 and the gun head 40. The fourth groove 3014 enables the second sealing ring 21 to be accurately accommodated at the connection and ensures that it is always in a pressed state during work, thereby achieving good sealing effect. By reasonably designing the size of the fourth groove 3014, it is ensured that the second sealing ring 21 will not be pressed out of the groove or lose its sealing effect during use, while maintaining good elasticity and sealing performance.

[0048] The fifth groove 3015 is used to accommodate the second step 403, which is a part of the gun head 40 and plays a supporting and fixing role at the connection between the cylinder body 30 and the gun head 40. The fifth groove 3015 can accommodate the second step 403, ensuring that it can stably cooperate with the cylinder body 30 during assembly and avoiding deviation or loosening during work. The size and depth of the fifth groove 3015 are matched with the outer shape of the second step 403, thereby ensuring that the step can be accurately embedded and ensuring the close cooperation of the sealing member and the assembly.

[0049] The sixth groove 3016 is used for accommodating the second pressing plate 22 and pressing the second step 403, the second pressing plate 22 is an important component, which is responsible for applying pressure to the second step 403, ensuring that the second sealing ring 21 is always in a state of being pressed, avoiding liquid or gas leakage, the function of the sixth groove 3016 is to accommodate the second pressing plate 22, ensure that it can be accurately positioned and not dislocated during the pressing process. By designing the appropriate size of the sixth groove 3016, the second pressing plate 22 can firmly press the second step 403, thereby further enhancing the sealing performance.

[0050] In a possible implementation, the connecting part of the cylinder body 30 and the gun head 40 is further provided with a push plate 23.

[0051] In the embodiment, the push plate 23 is located at the connecting part of the cylinder body 30 and the gun head 40, and its main function is to help the pipette complete the unloading and recycling functions of the TIP head. After the pipette completes the liquid suction and transfer, the TIP head needs to be taken out from the gun head 40 and reinstalled into the TIP head mounting hole of the reagent strip, and the push plate 23 helps to push the TIP head down from the gun head 40 by applying downward pressure, realizing the unloading process of the TIP head.

[0052] In a possible implementation, the connecting part of the cylinder body 30 and the gun head 40 is further provided with a push plate 23. Figure 4 As shown in the drawings, the utility model further provides a pipette 200, which comprises a pipette base plate 201, a lead screw driving part 202, a sliding block 203, a cylinder body 30, a piston rod 31, a gun head 40 and the sealing device 100 as described in the first aspect or any possible implementation of the first aspect, the pipette base plate 201 is provided with a guide rail 2011, the sliding block 203 is slidingly connected to the guide rail 2011 and connected to the piston rod 31, and the lead screw driving part 202 is drivingly connected to the sliding block 203 to drive the sliding block 203 to move the piston rod 31. The specific structure of the sealing device 100 is referred to the above-mentioned embodiments, since the pipette 200 adopts all the technical solutions of the above-mentioned embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here.

[0053] In this embodiment, the pipette base plate 201 serves as the bottom support structure of the pipette 200, responsible for providing a stable platform to support the other components of the entire pipette 200. It is usually connected with the cylinder 30 and other moving parts, and ensures the positional accuracy of the components during movement. The guide rail 2011 is designed on the pipette base plate 201, which provides a sliding track for the slider 203 to ensure smooth movement in the correct path. The guide rail 2011 is the track for the movement of the slider 203, ensuring smooth and accurate sliding of the slider 203 in the specified direction. The design of the guide rail 2011 usually has certain wear resistance and corrosion resistance to adapt to long-term work. The slider 203 is a moving component that cooperates with the guide rail 2011, and its main function is to convert the movement of the lead screw drive 202 into linear motion of the piston rod 31. The slider 203 is connected with the piston rod 31, so that the piston rod 31 can move up and down with the sliding of the slider 203. The slider 203 is connected with the base plate through the guide rail 2011, ensuring that it maintains a straight trajectory during movement and has stability. The lead screw drive 202 is the driving system of the entire pipette 200, responsible for generating linear motion by rotating to push the slider 203 to slide on the guide rail 2011. The lead screw drive 202 is often driven by an electric motor and achieves high-precision motion control through precise screw-nut cooperation. The lead screw drive 202 drives the nut connected with the slider 203 to move linearly by rotating the lead screw, thereby pushing the slider 203 to slide along the guide rail 2011 and further driving the piston rod 31 to move up and down. The piston rod 31 moves up and down through the cooperation with the inner cavity 301 of the cylinder 30. The up and down movement of the piston rod 31 is transmitted through the movement of the slider 203, ensuring that the pipette 200 can complete the suction and discharge of liquid. The outer part of the piston rod 31 is usually in interference fit with the sliding part 111 of the sealing sleeve ring 11, and the sealing device 100 ensures that there is no leakage of liquid or gas during the up and down movement of the piston rod 31. The piston rod 31 closely cooperates with the sealing device 100, ensuring the sealing of the pipette 200 and the accuracy of the liquid suction. The cylinder 30 is the carrier for the sliding of the piston rod 31, and its inner cavity 301 cooperates with the movement of the piston rod 31, and is usually equipped with appropriate sealing device 100 to prevent liquid or gas leakage. The gun head 40 is connected at the end of the cylinder 30, and is usually used to connect and control the suction head (such as TIP head). The gun head 40 is sealingly connected with the cylinder 30, ensuring that the liquid can be accurately transferred from the inside of the pipette 200 to the outside container or sample. In the structure of the pipette 200, the design of the sealing device 100 is crucial to ensure that the inner cavity 301 of the pipette 200 and the external environment maintain good sealing during the up and down movement of the piston rod 31, preventing liquid leakage. The precise cooperation of the sealing components such as the sealing sleeve ring 11, the sealing ring and the pressing plate ensures the sealing effect during the suction and discharge of liquid, ensuring the high-precision operation of the pipette 200.The screw driving part 202 drives the sliding block 203 to move, and the sliding block 203 drives the piston rod 31 to move up and down through the connection with the piston rod 31, forming the liquid suction and discharge action. During the movement of the piston rod 31, the sealing device 100 can effectively prevent the leakage of liquid or gas, and ensure that the pipette 200 can complete the liquid transfer, suction and discharge under precise control. Through the high-precision control of the screw driving part 202, the pipette 200 can complete the precise liquid suction and discharge. The movement trajectory of the sliding block 203 is stable, which can ensure that the piston rod 31 moves up and down along the predetermined path. The precise cooperation of the sealing device 100, the piston rod 31 and the cylinder body 30 avoids the leakage of liquid or gas, and ensures the long-term stable use of the pipette 200. By combining the sealing device 100, the mechanical driving system and the precise operation mechanism, the pipette 200 of the present application can efficiently and stably perform the liquid transfer task, and is widely used in laboratory, industry and biomedical field.

[0054] The same or similar reference numerals in the drawings of the embodiments correspond to the same or similar components; in the description of the present application, it should be understood that if the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right" and the like are based on the orientations or positional relationships shown in the drawings, they are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore the terms describing the positional relationship in the drawings are only used for exemplary illustration, and cannot be understood as a limitation of the present patent, for those skilled in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0055] The above is only the preferred embodiment of the present application, and does not limit the present application, any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A sealing device applied to a pipette, the pipette comprising a cylinder, a piston rod and a gun head, the cylinder being provided with an inner cavity, the piston rod being slidingly connected to the inner cavity, the gun head being provided with an inner hole, the gun head being connected to the cylinder, the inner hole being communicated with the inner cavity, characterized in that, The sealing device comprises: A first sealing assembly arranged at one end of the inner cavity away from the gun head, the first sealing assembly comprising a sealing ring, a first pressing plate and a first sealing ring, the sealing ring being embedded in the inner cavity, part of the first pressing plate being embedded in the inner cavity and abutting against the sealing ring, the sealing ring being in interference fit with the outer diameter of the piston rod, and the first sealing ring being sleeved on the outer wall of the sealing ring to apply radial compression force to the sealing ring; and A second sealing assembly arranged at the connection between the cylinder body and the gun head, the second sealing assembly comprising a second sealing ring and a second pressing plate and a push plate, the second sealing ring being sleeved on the gun head, and the second pressing plate being embedded in the cylinder body and pressing the gun head.

2. The sealing device of claim 1, wherein The sealing ring comprises a sliding part and a ring pressing part, the ring pressing part being in clearance fit with the piston rod, and the sliding part being in interference fit with the piston rod, and the first sealing ring being sleeved on the outer wall of the sliding part.

3. The sealing device of claim 2, wherein, The material of the sealing ring is polyoxymethylene, polyamide or polytetrafluoroethylene. The material of the piston rod is ceramic.

4. The sealing device of claim 3, wherein The wall thickness of the sliding part is 0.3-0.5mm.

5. The sealed device of claim 2, wherein, The position where the inner cavity is mounted with the first sealing assembly is provided with a first groove, a second groove and a third groove, the sliding part being accommodated in the first groove, the first sealing ring being accommodated in the second groove, and part of the ring pressing part and the first pressing plate being accommodated in the third groove.

6. The sealed device of claim 1, wherein, The connection between the cylinder body and the gun head is provided with a fourth groove, a fifth groove and a sixth groove, the gun head comprising a first step and a second step, the second sealing ring being sleeved on the first step and accommodated in the fourth groove, the second step being accommodated in the fifth groove, and the second pressing plate being pressed against the second step and accommodated in the sixth groove.

7. The sealed device of claim 1, wherein, The connection between the cylinder body and the gun head is further provided with a push plate.

8. A pipette, characterized in that The pipetting device comprises a pipetting base plate, a screw rod driving member, a sliding block, a cylinder body, a piston rod, a gun head and the sealing device according to any one of claims 1-7, the pipetting base plate being provided with a guide rail, the sliding block being slidingly connected to the guide rail and connected to the piston rod, and the screw rod driving member being drivingly connected to the sliding block to drive the sliding block to move the piston rod.

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