Pipette

Abstract

The pipettor comprises a shell, a driving assembly, a transmission assembly, a bearing assembly and a guiding assembly, a linear guide rail is arranged in the shell, a clamping assembly is arranged on the linear guide rail, the driving assembly controls movement of the transmission assembly through the clamping assembly, and the transmission assembly abuts against the clamping assembly when reset; the bearing assembly comprises a sealing body, one end of the sealing body is provided with a connecting shaft provided with a tip, and a through hole is formed in the connecting shaft. A sealing cavity for accommodating the transmission assembly and communicating with the through hole is formed in the sealing main body; the guide assembly comprises a main guide part and a guide rod assembly which is fixedly connected with the main guide part and penetrates through the sealing main body, and the guide rod assembly is fixedly connected with the push plate; the connecting shaft penetrates through the main guide part, and the main guide part has a moving freedom degree, so that the tip head is convenient to mount; the movement of the transmission assembly can be used for exhausting and extracting liquid; thrust generated by movement of the clamping assembly achieves automatic falling of the tip head through the main guiding piece. According to the scheme, simple, efficient and high-precision liquid pumping control can be realized.

Description

pipette Technical Field

[0001] This disclosure relates to the field of pipetting equipment technology, and more particularly to a pipette. Background Technology

[0002] In various experimental scenarios, pipettes are crucial experimental instruments, widely used in numerous fields such as biology, chemistry, and medicine. Their main function is to achieve precise transfer of minute amounts of liquid. However, current pipettes on the market have several significant problems, such as poor quantitative accuracy, complex structure, and high price. Furthermore, the existing types of pipette tips also have obvious limitations in liquid level detection. Ordinary transparent tips are not suitable for liquid level detection, while carbon-doped tips, although able to achieve liquid level detection with current methods, are expensive. All of these factors bring inconvenience to experimental operations and increase experimental costs. Summary of the Invention

[0003] In view of this, the present disclosure provides a pipette that at least partially solves the problems of existing pipettes being unable to achieve simple, efficient, and highly accurate rapid operation.

[0004] This disclosure provides a pipette, comprising:

[0005] A housing with a hollow cavity is provided inside the housing, and a linear guide rail is engaged on the linear guide rail;

[0006] Drive assembly; the engaging assembly has a degree of freedom to move along the longitudinal axis of the housing under the action of the drive assembly;

[0007] A transmission component has a degree of freedom of movement under the action of the engaging component, and one end of the transmission component abuts against the engaging component when the engaging component is in the reset state;

[0008] The carrier assembly includes a sealing body mounted on the other side of the housing. One end of the sealing body is provided with a connecting shaft for mounting a tip head, and the connecting shaft has a through hole inside. The sealing body has a sealing cavity inside that accommodates the transmission assembly and communicates with the through hole. The other end of the transmission assembly abuts against the sealing cavity when the engaging assembly is in a first state.

[0009] A guide assembly includes a main guide member and a guide rod assembly fixedly connected to the main guide member and passing through the sealing body. The end of the guide rod assembly is fixedly connected to a push plate sleeved on the outside of the transmission assembly. When the engagement assembly is in the second state, the push plate abuts against the engagement assembly and applies a release force to the tip head through the main guide member. A connecting shaft passes through the main guide member and the main guide member has a degree of freedom to move along the connecting shaft.

[0010] Optionally, the engaging assembly includes a slider and an engaging member fixedly mounted on the top of the slider; the bottom of the slider has an engaging groove that matches the linear guide rail.

[0011] The drive assembly includes a motor mounted on one side of the housing and a lead screw mounted on the power output end of the motor. The lead screw extends into the housing and passes through the engaging member. The engaging member has the freedom to move along the longitudinal central axis of the lead screw under the drive of the motor.

[0012] Optionally, the transmission assembly includes a sealing shaft with a countersunk hole and a thrust spring installed in the countersunk hole. One end of the thrust spring abuts against the engaging member when the engaging assembly is in the reset state, and the other end abuts against the bottom of the countersunk hole. The end of the sealing shaft is matched with the engaging member.

[0013] The longitudinal center axis of the countersunk hole, the longitudinal center axis of the sealing shaft, and the longitudinal center axis of the lead screw are aligned.

[0014] The countersunk hole has a length of h, where H / 2 < h < H, and H is the length of the sealing shaft.

[0015] Optionally, the engaging component includes a nut threadedly connected to the lead screw and an actuating block fixedly connected to the nut;

[0016] The working block includes a block body, a first cantilever arm located on one side of the block body, and a second cantilever arm, wherein the second cantilever arm is arranged parallel to the first cantilever arm;

[0017] The first cantilever arm has a first protrusion;

[0018] The second cantilever arm has a second protrusion;

[0019] The distance from the first protrusion to the block body is the same as the distance from the second protrusion to the block body.

[0020] Optionally, the sealing shaft includes a cylindrical section and a stop section fixed to the end of the countersunk hole, wherein the countersunk hole is located inside the cylindrical section;

[0021] The stop section includes a first engaging part and a second engaging part fixedly connected to the cylindrical section. The two sides of the first engaging part are respectively matched with the first cantilever arm and the second cantilever arm, and the two sides of the first engaging part have the degree of freedom to move along the first cantilever arm and the second cantilever arm.

[0022] The first protrusion and the second protrusion are both located on the side of the first engaging portion away from the engaging member, and the first protrusion and the second protrusion limit the first engaging portion when the engaging assembly is in the reset state;

[0023] The width of the first engaging portion is less than the distance from the first protrusion to the block body.

[0024] Optionally, the side portion of the first cantilever arm has a first thrust surface; the side portion of the second cantilever arm has a second thrust surface; the first thrust surface and the second thrust surface are symmetrically arranged with respect to the longitudinal central axis of the sealing shaft.

[0025] The push plate has a semi-circular hole, the inner diameter of which is larger than the outer diameter of the cylindrical segment, and the semi-circular hole is coaxially sleeved with the cylindrical segment; the distance between the outer side of the first protrusion and the outer side of the second protrusion is smaller than the inner diameter of the semi-circular hole.

[0026] The distance between the outer side of the first thrust action surface and the outer side of the second thrust action surface is greater than the inner diameter of the semi-circular hole;

[0027] When the engaging assembly is in the second state, the push plate abuts against the first and second thrust surfaces, and the first engaging portion is spaced apart from the first and second protrusions; under the action of the abutting force, the push plate pushes the main guide member to apply an outward release force to the end of the tip head.

[0028] Optionally, the sealing body is connected to the housing via a sealing assembly;

[0029] The sealing body has a through central hole inside, which includes a first hole segment, a second hole segment, a third hole segment, a fourth hole segment, and a fifth hole segment arranged in sequence. The first hole segment is threaded to the end of the connecting shaft.

[0030] The inner diameter of the second hole section is smaller than the inner diameter of the first hole section; the inner diameter of the third hole section is larger than the inner diameter of the first hole section; the inner diameter of the third hole section is matched with the outer diameter of the sealing shaft.

[0031] The inner diameter of the fourth hole segment is larger than the inner diameter of the third hole segment; the inner diameter of the fifth hole segment is larger than the inner diameter of the fourth hole segment;

[0032] The sealing assembly includes a sealing ring and a spacer ring, wherein the inner diameter of the spacer ring is larger than the inner diameter of the sealing ring, and the outer diameter of the spacer ring is larger than the outer diameter of the sealing ring.

[0033] The sealing ring is installed in the fourth hole section and abuts against the inner diameter of the fourth hole section; the spacer ring is installed in the fifth hole section and abuts against the inner diameter of the fifth hole section, and the side of the spacer ring abuts against the sealing ring; the inner diameter of the sealing ring abuts against the outer diameter of the sealing shaft, and the inner diameter of the spacer ring is provided with a gap from the outer diameter of the sealing shaft.

[0034] The sealing cavity is formed between the outer side of the sealing ring and the sealing shaft and the third hole section;

[0035] The volume of the sealed cavity is set to match the volume of the pipette.

[0036] Optionally, the sealing body has two guide holes symmetrically arranged with respect to the longitudinal central axis of the connecting shaft, and the longitudinal central axis of the guide holes is parallel to the longitudinal central axis of the lead screw.

[0037] The guide hole includes a first guide hole section and a second guide hole section. The inner diameter of the first guide hole section is larger than the inner diameter of the second guide hole section. A guide spring is provided inside the first guide hole section.

[0038] The guide rod assembly includes two guide rods that are matched with the two guide holes. One end of the guide rod is fixedly connected to the main guide member, and the other end passes through the guide spring and the second guide hole section and is fixedly connected to the push plate.

[0039] When the engaging assembly is in the reset state, the push plate does not contact the engaging member, the main guide member extends outward under the elastic force of the guide spring and is spaced apart from the side of the sealing body, and the push plate abuts against the inner wall of the housing.

[0040] Optionally, the connecting shaft has a tip head mounting portion;

[0041] The tip head mounting part includes a first arc-shaped engaging part and a second arc-shaped engaging part located on the outside of the connecting shaft and spaced apart. The first arc-shaped engaging part is located on the side of the second arc-shaped engaging part away from the sealing body.

[0042] The maximum outer diameter of the first arc-shaped engagement portion is smaller than the maximum outer diameter of the second arc-shaped engagement portion;

[0043] The distance between the second arc-shaped engaging part and the first arc-shaped engaging part is L1, the total length of the tip head is L2, 1 / 6≤L1 / L2≤1 / 4, and in the installed state, the first arc-shaped engaging part and the filter of the tip head do not interfere with each other.

[0044] Optionally, a cover plate is provided on the top of the housing;

[0045] A circuit board is disposed below the cover plate, and the circuit board is connected to the housing.

[0046] A photoelectric sensor and a barometric pressure sensor are installed below the circuit board.

[0047] A limit block is provided on the action block, and the motor is controlled to stop when the photoelectric sensor detects the limit block;

[0048] The pressure sensor is connected to the sealed cavity and is used to detect the pressure inside the sealed cavity.

[0049] The pipette disclosed in this application achieves movement control of the transmission and guiding components through a drive component, enabling precise control of the tip tip's venting, aspiration, drainage, and automatic detachment, increasing the accuracy of liquid movement within the instrument, reducing the complexity of the structural design, and effectively improving work efficiency. Before liquid aspiration, the drive assembly moves the locking assembly to the left, causing the sealing shaft to expel air from the sealed cavity and inside the tip tip under the action of the thrust spring. This process ensures that residual air will not affect subsequent liquid aspiration, guaranteeing the accuracy of liquid aspiration volume and laying the foundation for precise pipetting. During liquid aspiration, the drive assembly precisely controls the position of the transmission assembly, meeting the precise liquid volume requirements of different experiments and improving the reliability of experimental results. During liquid discharge, the drive assembly controls the movement distance of the transmission assembly within the sealed cavity, precisely controlling the amount of liquid discharged from the tip tip. By controlling the movement of the guide assembly through the drive assembly, automatic tip detachment control is achieved, eliminating the need for manual removal and effectively saving time, especially in experimental scenarios requiring frequent tip tip replacement. After the tip tip is detached, the pipette automatically resets, preparing for the next operation. This automatic reset function ensures the continuity of pipetting operation, allowing the instrument to quickly proceed to the next round of pipetting work and improving overall operational efficiency.

[0050] The above description is merely an overview of the technical solution disclosed herein. In order to better understand the technical means of this disclosure and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this disclosure more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0051] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0052] Figure 1 is a schematic diagram of the structure of a pipette provided in an embodiment of this disclosure.

[0053] Figure 2 is an explosion diagram of a pipette provided in an embodiment of this disclosure.

[0054] Figure 3 is a cross-sectional view of a pipette provided in an embodiment of this disclosure.

[0055] Figure 4 is a schematic diagram of the installation of the transmission assembly, the load-bearing assembly and the guide assembly provided in the embodiments of this disclosure when the engaging assembly is in the reset state.

[0056] Figure 5 is an assembly diagram of a portion of the components provided in this embodiment of the present disclosure, cut along the longitudinal central axis of the second support rod.

[0057] Figure 6 is a schematic diagram of the installation of the engaging component and the stop section provided in the embodiment of this disclosure.

[0058] Explanation of reference numerals in the attached figures:

[0059] 100. Housing; 110. Housing; 120. Circuit board; 121. Pressure sensor; 130. Linear guide rail;

[0060] 210. Engaging component; 211. Nut; 212. Actuating block; 2121. Block body; 2122. First cantilever arm; 2123. Second cantilever arm; 2124. First protrusion; 2125. Second protrusion; 2126. First thrust surface; 2127. Second thrust surface; 220. Slider;

[0061] 300. Drive assembly; 310. Motor; 320. Lead screw;

[0062] 410. Sealing shaft; 411. Cylindrical section; 412. Stop section; 4121. First engaging part; 4122. Second engaging part; 420. Thrust spring;

[0063] 510. Sealing body; 520. Connecting shaft; 521. First arc-shaped engagement part; 522. Second arc-shaped engagement part; 530. Sealing ring; 540. Spacer ring;

[0064] 610. Main guide component; 611. Hollow cylindrical part; 612. Plate-shaped force-bearing part; 613. First sub-guide cylinder; 614. Second sub-guide cylinder; 620. First straight rod; 630. Second straight rod; 640. First spring; 650. Second spring; 660. Push plate;

[0065] 710. Limit block;

[0066] 800, tip header. Detailed Implementation

[0067] The present disclosure will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the disclosure. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present disclosure are shown in the accompanying drawings.

[0068] It should be noted that, where there is no conflict, the embodiments and features described in this disclosure can be combined with each other. The technical solutions of this disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0069] Unless otherwise stated, the exemplary implementations / embodiments shown are to be understood as providing exemplary features of various details that provide ways in which the technical concepts of this disclosure can be implemented in practice. Therefore, unless otherwise stated, the features of various implementations / embodiments may be additionally combined, separated, interchanged and / or rearranged without departing from the technical concepts of this disclosure.

[0070] The use of crosshairs and / or shading in the accompanying drawings is generally used to clarify the boundaries between adjacent components. Thus, unless otherwise stated, the presence or absence of crosshairs or shading does not convey or indicate any preference or requirement for the specific material, material properties, dimensions, proportions, commonalities between the illustrated components, or any other characteristics, properties, etc., of the components. Furthermore, in the accompanying drawings, the dimensions and relative dimensions of components may be exaggerated for clarity and / or descriptive purposes. When exemplary embodiments can be implemented differently, a specific process sequence may be performed in a different order than that described. For example, two consecutively described processes may be performed substantially simultaneously or in the reverse order of their description. Furthermore, the same reference numerals denote the same components.

[0071] When a component is referred to as being "on" or "above" another component, "connected to," or "joined to" another component, the component may be directly on, directly connected to, or directly joined to the other component, or there may be intermediate components. However, when a component is referred to as being "directly on" another component, "directly connected to," or "directly joined to" another component, there are no intermediate components. Therefore, the term "connection" can refer to a physical connection, an electrical connection, etc., and may or may not have intermediate components.

[0072] For descriptive purposes, this disclosure may use spatial relative terms such as “below,” “under,” “below,” “down,” “above,” “above,” “higher,” and “side (e.g., in a “sidewall”)” to describe the relationship between one component and another component as shown in the accompanying drawings. In addition to the orientations depicted in the drawings, the spatial relative terms are also intended to encompass different orientations of the device during use, operation, and / or manufacture. For example, if the device in the drawings is flipped, a component described as “below” or “under” another component or feature would subsequently be positioned “above” said other component or feature. Thus, the exemplary term “below” can encompass both “above” and “below” orientations. Furthermore, the device may be otherwise positioned (e.g., rotated 90 degrees or in other orientations), thus interpreting the spatial relative descriptive terms used herein accordingly.

[0073] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, unless the context clearly indicates otherwise, the singular forms “a” and “the” are intended to include the plural forms as well. Furthermore, when the terms “comprising” and / or “including” and variations thereof are used in this specification, it indicates the presence of the stated features, integrals, steps, operations, parts, components, and / or groups thereof, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, parts, components, and / or groups thereof. It should also be noted that, as used herein, the terms “substantially,” “about,” and other similar terms are used as approximate terms rather than as terms of degree, thus explaining the inherent biases in measurements, calculated values, and / or provided values ​​that would be recognized by one of ordinary skill in the art.

[0074] Referring to Figures 1 and 2, this application discloses a pipette, including a housing 100, a locking assembly, a driving assembly 300, a transmission assembly, a carrying assembly, and a guiding assembly, for quick installation of a tip 800, liquid aspiration control of the tip 800, liquid discharge control of the tip 800, and automatic detachment control of the tip 800.

[0075] The outer casing 100 includes a housing 110 with a hollow cavity and a cover plate (not shown) disposed above the housing 110. The cover plate is closable and installed above the housing 110 to seal the housing 110, preventing dust, debris, etc. from entering the interior, protecting the internal components and extending the pipette's service life. A linear guide rail 130 is provided inside the housing 110. The engaging assembly is disposed on the linear guide rail 130 and has the freedom to move along the longitudinal axis of the linear guide rail 130. The linear guide rail 130 provides a precise movement path for the engaging assembly, ensuring stable movement along the longitudinal axis and improving the stability and accuracy of pipette operation. A circuit board 120 is also disposed below the cover plate, connected to the housing. This circuit board can be used to control the start and stop of the drive assembly 300.

[0076] The engaging assembly has the freedom to move along the longitudinal axis of the housing 110 under the action of the driving assembly 300. Specifically, the engaging assembly includes a slider 220 and an engaging member 210 fixedly installed on the top of the slider 220. The bottom of the slider 220 is provided with an engaging groove that matches the linear guide rail 130. The slider 220 has the freedom to slide along the linear guide rail 130. The engaging groove allows the slider 220 to slide smoothly along the linear guide rail 130, ensuring the stability and accuracy of the movement of the engaging assembly.

[0077] The engaging component 210 includes a nut 211 threadedly connected to the lead screw 320 and an action block 212 fixedly connected to the nut 211. When the motor 310 drives the lead screw 320 to rotate, the engaging component 210 can move along the longitudinal central axis of the lead screw 320 to realize the drive control of the transmission components and other parts.

[0078] A limit block 710 is provided on the action block 212, and a photoelectric sensor is provided below the circuit board 120. When the photoelectric sensor detects the limit block 710, it controls the motor 310 to stop, at which point the locking assembly is in a reset state. The limit block 710 is preferably an L-shaped reset sheet metal, which facilitates accurate sensing by the photoelectric sensor and ensures that the locking assembly returns to its initial position after each operation, preparing for the next operation and improving the repeatability and accuracy of the pipette.

[0079] The drive assembly 300 includes a motor 310 mounted on one side of the housing 110 and a lead screw 320 mounted on the power output end of the motor 310. The lead screw 320 extends into the housing 110 and passes through the engaging member 210. Under the drive of the motor 310, the engaging member 210 has the freedom to move along the longitudinal central axis of the lead screw 320. That is, the lead screw 320 passes through the engaging member 210, converting the rotational motion of the motor 310 into the linear motion of the engaging assembly. The structure is simple and the transmission efficiency is high, which can accurately control the moving position and speed of the engaging assembly.

[0080] The transmission component has a degree of freedom of movement under the action of the engaging component, and one end of the transmission component is pressed against the engaging component when the engaging component is in the reset state.

[0081] The support assembly includes a sealing body 510 mounted on the other side of the housing 110. One end of the sealing body 510 is equipped with a connecting shaft 520 for mounting the tip head 800. The connecting shaft 520 has a through hole inside. The sealing body 510 has a sealing cavity inside that accommodates the transmission assembly and communicates with the through hole. The other end of the transmission assembly abuts against the sealing cavity when the engagement assembly is in the first state.

[0082] The guide assembly includes a main guide member 610 and a guide rod assembly fixedly connected to the main guide member 610 and passing through the sealing body 510. The end of the guide rod assembly is fixedly connected to a push plate 660 sleeved on the outside of the transmission assembly. When the engagement assembly is in the second state, the push plate 660 abuts against the engagement assembly and applies a release force to the tip head 800 through the main guide member 610. That is, the main guide member 610 has a release force on the tip head 800 under the action of the abutting force, which can realize the automatic release of the tip head 800.

[0083] Furthermore, the connecting shaft 520 is disposed through the main guide member 610, and the main guide member 610 has the freedom to move along the connecting shaft 520. Specifically, when the tip head 800 is installed with the connecting shaft 520, when the tip head 800 is controlled to be fitted onto the free end of the connecting shaft 520, a thrust will be generated on the main guide member 610 that is close to the sealing body 510. When the tip head 800 and the connecting shaft 520 are installed in place, the side of the main guide member 610 and the sealing body 510 are in a tight fit.

[0084] Referring to Figure 3, the transmission assembly includes a sealing shaft 410 with a countersunk hole and a thrust spring 420 installed in the countersunk hole, wherein the opening of the countersunk hole is oriented toward the engaging member 210.

[0085] One end of the thrust spring 420 abuts against the side of the engaging member 210 when the engaging assembly is in the reset state, and the other end abuts against the bottom of the countersunk hole. That is, the thrust spring 420 has a certain preload in the initial state, which can generate a leftward thrust on the sealing shaft 410.

[0086] The end of the sealing shaft 410 is matched with the engaging member 210. The engaging member 210 forms a stop force on the sealing shaft 410 to prevent it from moving to the left. In this way, the engaging member 210 and the thrust spring 420 ensure that the position of the sealing shaft 410 is in the preset position. This allows for precise control of the stopping position and moving distance of the sealing shaft 410 within the sealing body 510, thereby enabling precise control of the amount of liquid drawn from the tip head 800.

[0087] The longitudinal center axis of the countersunk hole, the longitudinal center axis of the sealing shaft 410, and the longitudinal center axis of the lead screw 320 are aligned to ensure that the thrust direction of the thrust spring 420 on the sealing shaft 410 is accurate. This allows for precise control of the stopping position and moving distance of the sealing shaft 410 within the sealing body 510, thereby precisely controlling the amount of liquid drawn from the tip head 800.

[0088] The countersunk hole has a length of h, where H / 2 < h < H, and H is the length of the sealing shaft. This increases the contact area between the thrust spring and the sealing shaft, ensuring the thrust effect of the thrust spring on the sealing shaft.

[0089] In this embodiment, the sealing body 510 is connected to the housing 110 through a sealing assembly. The sealing assembly includes a sealing ring 530 and a spacer ring 540. The inner diameter of the spacer ring 540 is larger than the inner diameter of the sealing ring 530, and the outer diameter of the spacer ring 540 is larger than the outer diameter of the sealing ring 530.

[0090] The sealing body 510 has a through central hole inside, which includes a first hole segment, a second hole segment, a third hole segment, a fourth hole segment, and a fifth hole segment arranged in sequence. The first hole segment is threaded to the end of the connecting shaft 520 for stable installation of the connecting shaft 520.

[0091] The inner diameter of the second hole section is smaller than that of the first hole section; the inner diameter of the third hole section is larger than that of the first hole section; the inner diameter of the third hole section is matched with the outer diameter of the sealing shaft 410; wherein, the second hole section is used to ensure the connection between the third hole section and the first hole section, and at the same time ensure that the moving sealing shaft 410 in the third hole section will not affect the connecting shaft 520.

[0092] The inner diameter of the fourth hole section is larger than that of the third hole section; the inner diameter of the fifth hole section is larger than that of the fourth hole section; the sealing ring 530 is installed in the fourth hole section and abuts against the inner diameter of the fourth hole section, and the inner diameter of the sealing ring 530 abuts against the outer diameter of the sealing shaft 410, which is used to ensure the sealing of the left side chamber of the sealing shaft 410 during the movement process.

[0093] The spacer ring 540 is installed in the fifth hole section and abuts against the inner diameter of the fifth hole section. The side of the spacer ring 540 abuts against the sealing ring 530 to fix the sealing ring 530. The gap between the inner diameter of the spacer ring 540 and the outer diameter of the sealing shaft 410 is set to ensure that the setting of the spacer ring 540 will not affect the movement of the sealing shaft 410.

[0094] In this embodiment, the inner diameter of the spacer ring 540 is spaced apart from the sealing shaft 410, with a preferred single-sided gap of 0.01mm-0.03mm, which serves to guide the sealing shaft 410.

[0095] A sealing cavity is formed between the outer side of the sealing ring 530 and the sealing shaft 410 and the third hole section. In this embodiment, since the gap between the outer diameter of the sealing shaft 410 and the inner diameter of the third hole section is very small, the sealing cavity can be assumed to refer to the chamber to the left of the end of the sealing shaft 410 inside the third hole section. The volume of the sealing cavity is matched with the volume of the pipette. Because the movement position of the sealing shaft 410 can be controlled, the actual capacity of the sealing cavity can be precisely controlled, that is, the amount of liquid drawn into the tip 800 can be precisely controlled.

[0096] In this embodiment, the volume of the tip head 800 internal component is preferably the same as the actual volume of the sealed cavity when the engagement assembly is in the reset state.

[0097] Furthermore, the maximum distance the sealing shaft can move within the sealing cavity is ΔL, where ΔL = pipette volume V ÷ S sealing shaft bottom area.

[0098] Furthermore, if we consider the through holes in the first hole section, the second hole section, and the connecting shaft during the air purging process, we can also set △L = (pipette volume V + △V) ÷ S sealing shaft bottom area, where pipette volume V × 5% ≤ △V ≤ pipette volume V × 10%.

[0099] In this embodiment, the starting of the motor 310 is preferably controlled by the number of pulses.

[0100] In this embodiment, the connecting shaft 520 has a tip head mounting portion; the tip head mounting portion includes a first arc-shaped engaging portion 521 and a second arc-shaped engaging portion 522 located on the outside of the connecting shaft 520 and spaced apart, the first arc-shaped engaging portion 521 being located on the side of the second arc-shaped engaging portion 522 away from the sealing body 510.

[0101] The maximum outer diameter of the first arc-shaped engagement part 521 is smaller than the maximum outer diameter of the second arc-shaped engagement part. That is, the line connecting the outermost point of the first arc-shaped engagement part 521 and the outermost point of the second arc-shaped engagement part is an oblique line. The slope of this oblique line is consistent with the slope of the side wall of the tip head 800, which is used to ensure the matching setting with the inner side wall of the tip head 800 and ensure the installation seal.

[0102] The distance between the second arc-shaped engaging part 522 and the first arc-shaped engaging part 521 is L1, and the total length of the tip head 800 is L2. 1 / 6≤L1 / L2≤1 / 4, and in the installed state, the first arc-shaped engaging part 521 and the filter of the tip head 800 do not interfere with each other, thus avoiding damage to the filter; at the same time, it can achieve double sealing with different positions of the inner wall of the tip head 800, ensuring the installation sealing and the stability of the tip head 800.

[0103] When the engagement assembly is in the reset state, the second arc-shaped engagement portion 522 does not fully protrude from the through hole of the connecting shaft 520. Therefore, when the tip head 800 is engaged and fixed with the second arc-shaped engagement portion 522, it will push the main guide member 610 to move to the right relative to the connecting shaft 520.

[0104] In this embodiment, the ratio of the inner diameter of the through hole to the outer diameter of the connecting shaft 520 is Δ1, where 1 / 6 ≤ Δ1 ≤ 1 / 3, and preferably Δ1 is 1 / 5. Through the elongated through hole, the air pressure generated when the sealing shaft 410 moves to the left within the sealing cavity can be stably applied to the tip head 800, achieving stable air pressure discharge.

[0105] Furthermore, the side of the sealing body 510 has a protruding surface for guiding the movement of the main guide member 610, and the inner hole of the protruding surface can guide the connecting shaft 520 to ensure concentricity.

[0106] Furthermore, a pressure sensor 121 is also provided below the circuit board 120. The pressure sensor is connected to the sealed cavity and is used to detect the air pressure inside the sealed cavity, that is, the air pressure inside the nozzle can be known in real time, and the amount of solution drawn can be determined by the air pressure change. Specifically, one port of the pressure sensor is connected to the atmosphere, and the other port is connected to the chamber of the sealed cavity and sealed by a sealing ring.

[0107] Referring to Figures 4 and 5, the action block 212 includes a block body 2121, a first cantilever arm 2122 located on one side of the block body 2121, and a second cantilever arm 2123. The second cantilever arm 2123 is arranged parallel to the first cantilever arm 2122, and the tops of the second cantilever arm 2123 and the first cantilever arm 2122 are lower than the top of the block body 2121.

[0108] The first cantilever arm 2122 has a first protrusion 2124, and the second cantilever arm 2123 has a second protrusion 2125. The distance from the first protrusion 2124 to the block body 2121 is the same as the distance from the second protrusion 2125 to the block body 2121.

[0109] Preferably, the first protrusion 2124 is located at the end of the first cantilever arm 2122 and is disposed above the top of the first cantilever arm 2122; the second protrusion 2125 is located at the end of the second cantilever arm 2123 and is disposed above the top of the second cantilever arm 2123.

[0110] The sealing shaft 410 includes a cylindrical section 411 and a stop section 412 fixed to the end of the countersunk hole, with the countersunk hole located inside the cylindrical section 411.

[0111] The stop section 412 includes a first engaging portion 4121 and a second engaging portion 4122 fixedly connected to the cylindrical section 411. The two sides of the first engaging portion 4121 are respectively matched with the first cantilever arm 2122 and the second cantilever arm 2123, and the two sides of the first engaging portion 4121 have the freedom to move along the first cantilever arm 2122 and the second cantilever arm 2123.

[0112] The width of the first engaging portion 4121 is less than the distance from the first protrusion 2124 to the block body 2121. That is, in this embodiment, a first smooth area is formed between the first protrusion 2124 and the side of the block body 2121, and a second smooth area is formed between the second protrusion 2125 and the side of the block body 2121. The first smooth area and the second smooth area provide areas for the stop section 412 to move.

[0113] The first protrusion 2124 and the second protrusion 2125 are both located on the side of the first engaging portion 4121 away from the engaging member 210. When the engaging assembly is in the reset state, the first protrusion 2124 and the second protrusion 2125 limit the first engaging portion 4121, that is, prevent the sealing shaft 410 from moving away from the motor 310.

[0114] Furthermore, the side of the first cantilever arm 2122 has a first thrust surface 2126; the side of the second cantilever arm 2123 has a second thrust surface 2127; the first thrust surface 2126 and the second thrust surface 2127 are symmetrically arranged with respect to the longitudinal central axis of the sealing shaft 410.

[0115] In this embodiment, the first protrusion 2124 and the second protrusion 2125 are located between the first thrust surface 2126 and the second thrust surface 2127.

[0116] Referring to Figures 2 and 5, the push plate 660 has a semi-circular hole. The inner diameter of the semi-circular hole is larger than the outer diameter of the cylindrical section 411 and also larger than the outer diameter of the stop section 412. The semi-circular hole is coaxially fitted with the cylindrical section 411 to ensure that the push plate 660 and the cylindrical section 411 are coaxial, while not affecting the movement of the cylindrical section 411.

[0117] The distance between the outer side of the first protrusion 2124 and the outer side of the second protrusion 2125 is less than the inner diameter of the semi-circular hole; the distance between the outer side of the first thrust surface 2126 and the outer side of the second thrust surface 2127 is greater than the inner diameter of the semi-circular hole.

[0118] Before the left side of the cylindrical section 411 moves to the left and into position, the actuating block 212 will not contact the push plate 660, and the right side of the first protrusion 2124 and the second protrusion 2125 will always be in a state of being pressed against the left side of the first engaging part 4121.

[0119] When the left side of the cylindrical section 411 moves to the left and into position, that is, when the left side of the sealing shaft 410 cannot move, the motor 310 controls the lead screw 320 to continue rotating, driving the engaging member 210 to continue moving to the left. At this time, the first protrusion 2124 and the second protrusion 2125 on the action block 212 move away from the first engaging part 4121 until they move to the first thrust action surface 2126 and the second thrust action surface 2127 and contact the push plate 660. Then, under the action of the leftward thrust, the push plate 660 will be pushed to the left as a whole by the first thrust action and the second thrust action surface 2127, and at the same time, the main guide member 610 fixedly connected to the push plate 660 will be provided with a leftward thrust. This thrust can be used to push the tip head 800 to fall off relative to the connecting shaft 520.

[0120] When the first thrust surface 2126 and the second thrust surface 2127 come into contact with the push plate 660, the first protrusion 2124 and the second protrusion 2125 extend into the area inside the semi-circular hole.

[0121] When the engaging assembly is in the second state, the push plate 660 abuts against the first thrust surface 2126 and the second thrust surface 2127, and the first engaging portion 4121 is spaced apart from the first protrusion 2124 and the second protrusion 2125. Under the action of the abutting force, the push plate 660 pushes the main guide member 610 to apply an outward release force to the end of the tip head 800. In this embodiment, the second state refers to the process in which the liquid inside the tip head 800 has been pushed out and the tip head 800 is controlled to automatically detach.

[0122] By applying a detachment force to the tip head 800 through the main guide component 610, the tip head 800 is automatically detached, avoiding the tediousness of manual operation and potential contamination, thus improving work efficiency and experimental safety.

[0123] Referring to Figures 2 and 6, the sealing body 510 has two guide holes symmetrically arranged relative to the longitudinal central axis of the connecting shaft 520. The longitudinal central axis of the guide holes is parallel to the longitudinal central axis of the lead screw 320, and the two guide holes do not interfere with each other and the through central hole.

[0124] Specifically, the guide hole includes a first guide hole section and a second guide hole section. The inner diameter of the first guide hole section is larger than the inner diameter of the second guide hole section. A guide spring is provided inside the first guide hole section. The outer diameter of the guide spring is larger than the inner diameter of the second guide hole section to prevent the guide spring from entering the second guide hole section.

[0125] The guide rod assembly includes two guide rods that are matched with two guide holes. One end of the guide rod is fixedly connected to the main guide member 610, and the other end passes through the guide spring and the second guide hole section and is fixedly connected to the push plate 660.

[0126] In this embodiment, the two guide rods are a first straight rod 620 and a second straight rod 630, and the corresponding two guide springs are a first spring 640 and a second spring 650.

[0127] When the engaging assembly is in the reset state, the push plate 660 does not contact the engaging member 210, and the main guide member 610 extends outward under the elastic force of the guide spring and is spaced apart from the side of the sealing body 510. The push plate 660 abuts against the inner wall of the housing 110.

[0128] Furthermore, the main guide member 610 includes a plate-shaped force-bearing part 612 and a hollow cylindrical part 611 located on one side of the plate-shaped force-bearing part 612. The plate-shaped force-bearing part 612 has a through hole, which is corresponding to the hollow part of the hollow cylindrical part 611. On the other side of the plate-shaped force-bearing part 612, a first sub-guide cylinder 613 and a second sub-guide cylinder 614 are provided, which are symmetrically arranged with respect to the through hole. Two guide rods are threadedly fixedly connected to the first sub-guide cylinder 613 and the second sub-guide cylinder 614, respectively. When the engaging assembly is in the reset state, the two guide springs apply an outward pushing force to the plate-shaped force-bearing part 612. At this time, the second arc-shaped engaging part 522 on the connecting shaft 520 does not completely protrude outside the through hole of the connecting shaft 520.

[0129] When the tip head 800 is not installed, the two guide springs are in a free state. The main guide member 610 is in a suspended state that does not contact the side of the sealing body 510 under the elastic force of the two guide springs to the left, and the push plate 660 is in a state of abutting against the left side of the inside of the housing 110.

[0130] When the tip head 800 is installed, the installation force of the tip head 800 and the connecting shaft 520 pushes the main guide member 610 to move to the right until it abuts against the outside of the sealing body 510. At this time, the push plate 660 is in a state of not contacting the inside of the housing 110; at the same time, the locking assembly is in a reset state.

[0131] Air purging state: Motor 310 starts, control screw 320 rotates forward, driving the engagement assembly to move to the left, forming a leftward thrust on thrust spring 420. Sealing shaft 410 moves to the left under the action of thrust spring 420 until it can no longer move or moves to the preset limit position set by the program. Through the movement of sealing shaft 410, the air in the sealing cavity is discharged, and the air inside tip head 800 is purged at the same time, preparing for subsequent liquid aspiration operations and ensuring the accuracy of liquid aspiration.

[0132] Extracting liquid: Immerse tip 800 into the liquid to be extracted, or first extract a preset amount of air (i.e., perform a dry evacuation), and then immerse tip 800 into the liquid to be extracted.

[0133] Liquid extraction process: The motor 310 starts, controlling the lead screw 320 to rotate in the opposite direction, driving the locking assembly to move to the right, which in turn drives the sealing shaft 410 to move to the right. The moving position of the sealing shaft 410 is matched with the preset amount to be extracted. Among them, the motor 310 is controlled by the number of pulses to achieve precise control of the moving distance of the sealing shaft 410, thereby controlling the suction volume of the tip head 800, meeting the precise requirements of different experiments for liquid volume.

[0134] Drainage process: After the pipette is moved to the target position, the motor 310 starts, controlling the lead screw 320 to rotate forward, driving the engagement assembly to move to the left, creating a leftward thrust on the push spring 420. The sealing shaft 410 moves to the left under the action of the push spring 420 until it can no longer move, thus draining the liquid from the tip 800. The operation is simple and the drainage is accurate. Alternatively, a preset amount of extracted liquid and a preset amount of air can be drained, achieving the effect of completely draining the solution.

[0135] Automatic tip detachment process: At this time, the sealing shaft 410 is immobile, the lead screw 320 continues to rotate forward, driving the engaging assembly to move to the left until it contacts the push plate 660, and exerts a leftward thrust on the push plate 660. The push plate 660 moves under the leftward thrust, and at the same time drives the main guide member 610 to move to the left. Since the connecting shaft 520, which is fixed to the sealing body 510, does not move, the side of the moved main guide member 610 will exert a leftward force on the end of the tip 800, thereby realizing the automatic detachment of the tip 800 relative to the connecting shaft 520, reducing manual operation, improving work efficiency, and avoiding contamination that may be caused by manual contact with the tip 800.

[0136] Reset: After the tip 800 falls off, the locking assembly resets. That is, under the drive of the motor 310, the lead screw 320 rotates in the opposite direction until the locking assembly is reset. At this time, the right side of the push plate 660 is not under force, and the main guide member 610 extends outward under the force of the guide spring. At this time, the guide spring is in a free extension state, and the main guide member 610 has a certain gap with the sealing body 510, returning to the initial position to prepare for the next operation, ensuring the continuity and stability of pipette operation.

[0137] The pipette disclosed in this application achieves movement control of the transmission and guiding components through a drive component, enabling precise control of the tip tip's venting, aspiration, drainage, and automatic detachment, increasing the accuracy of liquid movement within the instrument, reducing the complexity of the structural design, and effectively improving work efficiency. Before liquid aspiration, the drive assembly moves the locking assembly to the left, causing the sealing shaft to expel air from the sealed cavity and inside the tip tip under the action of the thrust spring. This process ensures that residual air will not affect subsequent liquid aspiration, guaranteeing the accuracy of liquid aspiration volume and laying the foundation for precise pipetting. During liquid aspiration, the drive assembly precisely controls the position of the transmission assembly, meeting the precise liquid volume requirements of different experiments and improving the reliability of experimental results. During liquid discharge, the drive assembly controls the movement distance of the transmission assembly within the sealed cavity, precisely controlling the amount of liquid discharged from the tip tip. By controlling the movement of the guide assembly through the drive assembly, automatic tip detachment control is achieved, eliminating the need for manual removal and effectively saving time, especially in experimental scenarios requiring frequent tip tip replacement. After the tip tip is detached, the pipette automatically resets, preparing for the next operation. This automatic reset function ensures the continuity of pipetting operation, allowing the instrument to quickly proceed to the next round of pipetting work and improving overall operational efficiency.

[0138] In the description of this specification, the references to terms such as "one embodiment / mode," "some embodiments / modes," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment / mode or example is included in at least one embodiment / mode or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment / mode or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments / modes or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments / modes or examples described in this specification, as well as the features of different embodiments / modes or examples.

[0139] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0140] Those skilled in the art should understand that the above embodiments are merely for illustrating the present disclosure and are not intended to limit the scope of the disclosure. Those skilled in the art can make other changes or modifications based on the above disclosure, and these changes or modifications still fall within the scope of the present disclosure.

Claims

1. A pipette, characterized in that, include: A housing with a hollow cavity is provided inside the housing, and a linear guide rail is provided on the linear guide rail. A locking assembly is engaged on the linear guide rail. A driving assembly is provided; the locking assembly has a degree of freedom to move along the longitudinal axis of the housing under the action of the driving assembly. A transmission assembly has a degree of freedom to move under the action of the locking assembly, and one end of the transmission assembly abuts against the locking assembly when the locking assembly is in a reset state. A bearing assembly includes a sealing body mounted on the other side of the housing, one end of which is equipped with a connecting shaft for mounting a tip head. The shaft has a through hole inside; the sealing body has a sealing cavity inside that accommodates the transmission assembly and communicates with the through hole; the other end of the transmission assembly is pressed against the sealing cavity when the engaging assembly is in the first state; the guide assembly includes a main guide member and a guide rod assembly fixedly connected to the main guide member and passing through the sealing body, the end of the guide rod assembly being fixedly connected to a push plate sleeved on the outside of the transmission assembly; the push plate is pressed against the engaging assembly when the engaging assembly is in the second state, and applies a release force to the tip head through the main guide member; The connecting shaft passes through the main guide member, and the main guide member has the freedom to move along the connecting shaft.

2. The pipette according to claim 1, characterized in that, The engaging assembly includes a slider and an engaging member fixedly mounted on the top of the slider; the bottom of the slider has an engaging groove that matches the linear guide rail; the driving assembly includes a motor mounted on one side of the housing and a lead screw mounted on the power output end of the motor, the lead screw extending into the housing and penetrating the engaging member; the engaging member has the freedom to move along the longitudinal central axis of the lead screw under the drive of the motor.

3. The pipette according to claim 2, characterized in that, The transmission assembly includes a sealing shaft with a countersunk hole and a thrust spring installed in the countersunk hole. One end of the thrust spring abuts against the engaging member when the engaging assembly is in the reset state, and the other end abuts against the bottom of the countersunk hole. The end of the sealing shaft is matched with the engaging member. The longitudinal center axis of the countersunk hole and the longitudinal center axis of the sealing shaft are aligned with the longitudinal center axis of the lead screw. The length of the countersunk hole is h, where H / 2 < h < H, and H is the length of the sealing shaft.

4. The pipette according to claim 3, characterized in that, The engaging component includes a nut threadedly connected to the lead screw and an actuating block fixedly connected to the nut; the actuating block includes a block body, a first cantilever arm located on one side of the block body, and a second cantilever arm, the second cantilever arm being arranged parallel to the first cantilever arm; the first cantilever arm has a first protrusion; the second cantilever arm has a second protrusion; the distance from the first protrusion to the block body is the same as the distance from the second protrusion to the block body.

5. The pipette according to claim 4, characterized in that, The sealing shaft includes a cylindrical section and a stop section fixed to the end of the countersunk hole, the countersunk hole being located inside the cylindrical section; the stop section includes a first engaging portion and a second engaging portion fixedly connected to the cylindrical section, the two sides of the first engaging portion being respectively matched with the first cantilever arm and the second cantilever arm, and the two sides of the first engaging portion having degrees of freedom to move along the first cantilever arm and the second cantilever arm; the first protrusion and the second protrusion are both located on the side of the first engaging portion away from the engaging member, and the first protrusion and the second protrusion form a limit on the first engaging portion when the engaging assembly is in the reset state; the width of the first engaging portion is less than the distance from the first protrusion to the block body.

6. The pipette according to claim 5, characterized in that, The first cantilever arm has a first thrust surface on its side; the second cantilever arm has a second thrust surface on its side; the first thrust surface and the second thrust surface are symmetrically arranged with respect to the longitudinal central axis of the sealing shaft; the push plate has a semi-circular hole, the inner diameter of which is larger than the outer diameter of the cylindrical segment, and the semi-circular hole is coaxially fitted with the cylindrical segment; the distance between the outer side of the first protrusion and the outer side of the second protrusion is smaller than the inner diameter of the semi-circular hole; the distance between the outer side of the first thrust surface and the outer side of the second thrust surface is larger than the inner diameter of the semi-circular hole; when the engaging assembly is in the second state, the push plate abuts against the first thrust surface and the second thrust surface, and the first engaging portion is spaced apart from the first protrusion and the second protrusion; under the action of the abutting force, the push plate pushes the main guide member to apply an outward unloading force to the end of the tip head.

7. The pipette according to claim 4, characterized in that, The sealing body is connected to the housing via a sealing assembly; the sealing body has a through central hole, which includes a first segment, a second segment, a third segment, a fourth segment, and a fifth segment arranged sequentially; the first segment is threaded to the end of the connecting shaft; the inner diameter of the second segment is smaller than that of the first segment; the inner diameter of the third segment is larger than that of the first segment; the inner diameter of the third segment matches the outer diameter of the sealing shaft; the inner diameter of the fourth segment is larger than that of the third segment; the inner diameter of the fifth segment is larger than that of the fourth segment; the sealing assembly includes... A sealing ring and a spacer ring are provided. The inner diameter of the spacer ring is larger than the inner diameter of the sealing ring, and the outer diameter of the spacer ring is larger than the outer diameter of the sealing ring. The sealing ring is installed in the fourth hole segment and abuts against the inner diameter of the fourth hole segment. The spacer ring is installed in the fifth hole segment and abuts against the inner diameter of the fifth hole segment, with its side abutting against the sealing ring. The inner diameter of the sealing ring abuts against the outer diameter of the sealing shaft, and a gap is provided between the inner diameter of the spacer ring and the outer diameter of the sealing shaft. A sealing cavity is formed between the outer side of the sealing ring and the sealing shaft and the third hole segment. The volume of the sealing cavity is matched to the volume of the pipette.

8. The pipette according to claim 7, characterized in that, The sealing body has two guide holes symmetrically arranged relative to the longitudinal central axis of the connecting shaft. The longitudinal central axis of the guide holes is parallel to the longitudinal central axis of the lead screw. The guide holes include a first guide hole section and a second guide hole section. The inner diameter of the first guide hole section is larger than the inner diameter of the second guide hole section. A guide spring is provided in the first guide hole section. The guide rod assembly includes two guide rods that are matched with the two guide holes. One end of the guide rod is fixedly connected to the main guide member, and the other end passes through the guide spring and the second guide hole section and is fixedly connected to the push plate. When the engaging assembly is in the reset state, the push plate does not contact the engaging member. The main guide member extends outward under the elastic force of the guide spring and is spaced apart from the side of the sealing body. The push plate abuts against the inner wall of the housing.

9. The pipette according to claim 1, characterized in that, The connecting shaft has a tip head mounting portion; the tip head mounting portion includes a first arc-shaped engaging portion and a second arc-shaped engaging portion located on the outside of the connecting shaft and spaced apart, the first arc-shaped engaging portion being located on the side of the second arc-shaped engaging portion away from the sealing body; the maximum outer diameter of the first arc-shaped engaging portion is smaller than the maximum outer diameter of the second arc-shaped engaging portion; the distance between the second arc-shaped engaging portion and the first arc-shaped engaging portion is L1, the total length of the tip head is L2, 1 / 6≤L1 / L2≤1 / 4, and in the installed state, the first arc-shaped engaging portion and the filter of the tip head do not interfere with each other.

10. The pipette according to claim 7, characterized in that, A cover plate is provided on the top of the housing; a circuit board is provided below the cover plate and connected to the housing; a photoelectric sensor and a pressure sensor are provided below the circuit board; a limit block is provided on the action block, and the motor is controlled to stop when the photoelectric sensor detects the limit block; the pressure sensor is connected to the sealing cavity and is used to detect the pressure inside the sealing cavity.

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