An automated pipetting mechanism for an immunoblotter

Abstract

The utility model discloses an automatic pipette mechanism of immunoblotting instrument relates to biological experiment equipment technical field. The automatic pipette mechanism of immunoblotting instrument, including frame, the frame top is equipped with horizontal installation plane and the surface milling plane, and the frame top both sides are fixedly connected with two X axle guide rails, and the X axle guide rail is linear guide rail structure and the section is I -shaped, the frame one side is fixedly connected with PLC controller, and the PLC controller is fixedly connected with the frame through four ground anchors of bottom, and simultaneously, the multichannel liquid suction needle is accurately positioned through the needle hole of pipette assembly mounting plate, and the needle tube is vertically downward and is perpendicular with the reaction groove plane, ensures the reagent vertical in -out when sucking liquid, adding liquid, avoids the reagent residue or reaction groove pollution caused by needle tube inclination, and guarantees the accuracy of experimental result.

Description

Technical Field

[0001] This utility model relates to the field of medical experimental technology, and in particular to an automatic pipetting mechanism for an immunoblotting instrument. Background Technology

[0002] In life science experiments, the pipetting operation of immunoblotting instruments requires extremely high positioning accuracy. For micro-samples, even a slight deviation in the pipetting position can cause reagents to be missed in the target reaction area, leading to distorted experimental results. Furthermore, experimental repeatability is crucial to the reliability of the data. Currently, traditional immunoblotting pipetting devices on the market lack a precise, automated moving structure, which is the core problem causing large positional errors and poor experimental repeatability in manual pipetting. Most traditional devices rely on purely manual pipetting, requiring experimenters to hold the aspirator or manually adjust the position using a knob, relying solely on visual observation to align the reaction tank. Slight hand tremors and visual fatigue can easily cause the aspirator to deviate from the target area, resulting in a single operation positional error far exceeding the positioning accuracy required for immunoblotting experiments. The few devices equipped with simple mechanical transmissions also lack the precise coordination between the linear guide rail and the ball screw. The guide rail has high frictional resistance, uneven transmission gaps, and no position feedback mechanism, making it easy for the pipetting components to jam or overshoot during movement. Manual adjustment makes it difficult to control the displacement.

[0003] Meanwhile, traditional equipment lacks an integrated automated movement unit. The movement of the X / Y / Z axes needs to be adjusted separately by independent manual knobs. The position of the aspiration needle needs to be recalibrated before each experiment. There are no quantitative parameter records during the adjustment process, and it relies solely on experience and feel. The positioning parameters of different operators or the same operator at different times are prone to differences, resulting in significant differences in experimental results. Utility Model Content

[0004] The purpose of this invention is to at least solve one of the technical problems existing in the prior art, and to provide an automatic pipetting mechanism for an immunoblotting instrument that can solve the above-mentioned problem.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an automatic pipetting mechanism for an immunoblotting instrument, comprising a frame, wherein the top of the frame is provided with a horizontal mounting plane and the surface is milled flat, and two X-axis guide rails are fixedly connected to both sides of the top of the frame, wherein the X-axis guide rails are linear guide rails with an I-shaped cross section;

[0006] An X-axis slider is slidably connected to one end of the X-axis guide rail away from the frame. An X-axis ball screw is rotatably connected to the connection between the X-axis slider and the X-axis guide rail. Bearing seats are rotatably connected to both ends of the X-axis ball screw. One end of the bearing seat is fixedly connected to the top of the frame.

[0007] One end of the X-axis ball screw is fixedly connected to an X-axis drive motor away from the bearing housing. A coupling is fixedly connected between the X-axis drive motor and the bearing housing. An L-shaped support frame is fixedly connected to the end of the X-axis drive motor away from the coupling by bolts. A frame is fixedly connected to the end of the L-shaped support frame away from the X-axis drive motor. A position sensor is fixedly connected to the end of the X-axis ball screw away from the X-axis drive motor on one side of the bearing housing.

[0008] The end of the X-axis slider away from the X-axis guide rail is fixedly connected to the Y-axis mounting plate, the end of the Y-axis mounting plate away from the X-axis slider is fixedly connected to the Y-axis guide rail, and the end of the Y-axis guide rail away from the Y-axis mounting plate is slidably connected to the Y-axis slider.

[0009] A Y-axis ball screw is rotatably connected at the connection between the Y-axis slider and the Y-axis guide rail. Bearing seats are rotatably connected to both ends of the Y-axis ball screw. The bearing seats are clearance-fitted with both ends of the Y-axis guide rail and one end is fixedly connected to the Y-axis mounting plate.

[0010] A Y-axis drive motor is fixedly connected to one end of the Y-axis ball screw away from the bearing housing. A motor mounting bracket is fixedly connected to the surface of the Y-axis drive motor near the Y-axis mounting plate. A position sensor is fixedly connected to the other end of the Y-axis ball screw away from the Y-axis drive motor on the side of the bearing housing.

[0011] The Y-axis slider is fixedly connected to an L-shaped Z-axis mounting base at one end away from the Y-axis guide rail. The Z-axis guide rail is fixedly connected to the inner side of the Z-axis mounting base at one end away from the Y-axis slider. The Z-axis slider is slidably connected to the Z-axis guide rail at one end away from the Z-axis mounting base.

[0012] A Z-axis ball screw is rotatably connected at the connection between the Z-axis slider and the Z-axis guide rail. Bearing seats are rotatably connected to both ends of the Z-axis ball screw, and one end of the bearing seat is fixedly connected to the Z-axis mounting base.

[0013] One end of the Z-axis ball screw is fixedly connected to a Z-axis drive motor away from the bearing housing, and the other end of the Z-axis ball screw away from the Z-axis drive motor is fixedly connected to a position sensor on one side of the bearing housing.

[0014] The end of the Z-axis slider away from the Z-axis guide rail is fixedly connected to a pipetting assembly mounting plate. The surface of the pipetting assembly mounting plate is provided with pinholes. A multi-channel aspiration needle is fixedly connected inside the pipetting assembly mounting plate. The multi-channel aspiration needles are arranged in a linear row and correspond one-to-one with the pinholes. The needle tubes of the multi-channel aspiration needles are vertically downward, and the top of the needle tubes are connected to the reagent storage tank and peristaltic pump of the immunoblotting instrument through silicone tubing.

[0015] A PLC controller is fixedly connected to one side of the frame, and the PLC controller is fixedly connected to the frame via four feet at the bottom.

[0016] Preferably, the two X-axis guide rails are arranged in parallel, and the length direction of the X-axis guide rails is consistent with the length direction of the horizontal mounting plane at the top of the frame.

[0017] Preferably, one end of the coupling is fixedly connected to the output end of the X-axis drive motor, and the other end is fixedly connected to the end of the X-axis ball screw, and the axis of the coupling is collinear with the axis of the X-axis ball screw.

[0018] Preferably, the length direction of the Y-axis guide rail is perpendicular to the length direction of the X-axis guide rail, and the Y-axis guide rail is fixedly attached to the side of the Y-axis mounting plate away from the X-axis slider.

[0019] Preferably, the end of the multi-channel aspiration needle that is away from the pipetting assembly mounting plate is located directly above the reaction chamber of the immunoblotting instrument, and the needle tube is perpendicular to the plane of the reaction chamber.

[0020] Preferably, the L-shaped structure of the Z-axis mounting base includes a horizontal section and a vertical section. The horizontal section is fixedly connected to the end of the Y-axis slider away from the Y-axis guide rail, and the inner side of the vertical section is fixedly connected to the Z-axis guide rail.

[0021] Preferably, the X-axis ball screw, Y-axis ball screw, and Z-axis ball screw have the same structure, and their axes are parallel to the length directions of the X-axis guide rail, Y-axis guide rail, and Z-axis guide rail, respectively.

[0022] Preferably, the end of the motor mounting base away from the Y-axis drive motor is fixedly connected to the side of the Y-axis mounting plate away from the Y-axis guide rail, and the axis of the motor mounting base is parallel to the axis of the Y-axis ball screw.

[0023] Compared with the prior art, the beneficial effects of this utility model are:

[0024] 1. The automatic pipetting mechanism of this immunoblotting instrument adopts a linear guide structure for the X-axis guide rail on the top of the frame, the Y-axis guide rail on the Y-axis mounting plate, and the Z-axis guide rail on the Z-axis mounting base. It is equipped with ball screws for each axis, resulting in small transmission backlash and high precision. Furthermore, each axis ball screw is fixed with a position sensor at one end, which can collect the position data of the slider on the X-axis, Y-axis, and Z-axis in real time and feed it back to the PLC controller to achieve closed-loop control of the three-axis displacement, avoiding the positioning errors caused by manual operation or mechanical loosening in traditional pipetting. In terms of stability, the X-axis drive motor is fixed to the frame via an L-shaped support bracket, and the Y-axis drive motor is connected to the Y-axis mounting plate via a motor mounting bracket. Each drive motor is securely installed, reducing vibration transmission during operation. Meanwhile, the multi-channel aspiration needle is precisely positioned through the pinholes on the pipetting assembly mounting plate. The needle tube is vertically downward and perpendicular to the plane of the reaction tank, ensuring that reagents enter and exit vertically during aspiration and addition, avoiding reagent residue or reaction tank contamination caused by needle tilting, and ensuring the accuracy of experimental results.

[0025] 2. The automated pipetting mechanism of this immunoblotting instrument features a linear array of multi-channel aspiration needles on the pipetting assembly mounting plate, allowing simultaneous aspiration and dispensing of liquid into multiple reaction chambers. Compared to traditional single-channel pipetting, this significantly reduces sample processing time, allowing for processing one sample at a time. Furthermore, the PLC controller can preset pipetting programs, achieving a fully automated process for positioning, aspiration, and dispensing, minimizing manual intervention and avoiding human error such as inconsistent dispensing volumes or uneven operation intervals. In terms of compatibility, the multi-channel aspiration needles are connected to the reagent tank and peristaltic pump via silicone tubing, not mechanically fixed. When changing to different needle sizes, there is no need to disassemble the complex mechanical structure; only the tubing and needle body need to be replaced to adapt to different reagent or reaction chamber specifications, enhancing the instrument's versatility. In terms of maintenance, both ends of each axis ball screw are rotatably connected by bearing housings. The bearing housings are fixedly connected to the frame and mounting plate. During disassembly and assembly, only the bearing housings need to be removed to maintain the ball screws. At the same time, the silicone tubing is flexibly connected, which is not easily damaged by vibration aging. The tubing can be removed separately for cleaning, without the need to disassemble the entire pipetting assembly, reducing maintenance difficulty and downtime, and ensuring the continuity of experiments. Attached Figure Description

[0026] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0027] Figure 1 This is a schematic diagram of the automatic pipetting mechanism of an immunoblotting instrument according to the present invention;

[0028] Figure 2 This is a schematic diagram of the automatic pipetting mechanism of an immunoblotting instrument according to the present invention;

[0029] Figure 3 This is a schematic diagram of the automatic pipetting mechanism of an immunoblotting instrument according to the present invention;

[0030] Figure 4 This is a schematic diagram of the automatic pipetting mechanism of an immunoblotting instrument according to the present invention.

[0031] Reference numerals: 1. Frame; 2. L-shaped support frame; 3. X-axis drive motor; 4. Z-axis drive motor; 5. Bearing housing; 6. X-axis guide rail; 7. X-axis ball screw; 8. Y-axis mounting plate; 9. Position sensor; 10. X-axis slider; 11. Y-axis slider; 12. Z-axis mounting base; 13. Z-axis slider; 14. Pipette assembly mounting plate; 15. Y-axis guide rail; 16. Y-axis ball screw; 17. Multi-channel suction needle; 18. PLC controller; 19. Z-axis guide rail; 20. Y-axis drive motor; 21. Coupling; 22. Motor mounting base; 23. Z-axis ball screw. Detailed Implementation

[0032] This section will describe in detail the specific embodiments of the present utility model. The preferred embodiments of the present utility model are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present utility model, but they should not be construed as limiting the scope of protection of the present utility model.

[0033] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0034] In the description of this utility model, terms such as greater than, less than, and exceeding are understood to exclude the stated number, while terms such as above, below, and within are understood to include the stated number. The use of terms like "first" and "second" is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the quantity or sequence of the indicated technical features.

[0035] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0036] Please see Figure 1-4 This utility model provides a technical solution: an automatic pipetting mechanism for an immunoblotting instrument includes a frame 1. The top of the frame 1 has a horizontally milled mounting plane. Two X-axis guide rails 6 are fixedly connected to both sides of the top of the frame 1. Both X-axis guide rails are linear guide rails with an I-shaped cross-section. The milled mounting plane ensures the installation accuracy of the X-axis guide rails 6, preventing tilting due to unevenness and laying the foundation for subsequent precise triaxial displacement. The linear guide rail structure of the X-axis guide rails 6 has a small transmission clearance, which significantly reduces frictional resistance compared to traditional sliding guide rails, improves the smoothness of slider movement, and reduces positioning errors.

[0037] X-axis guide rail 6 is slidably connected to an X-axis slider 10 at its end away from the frame 1. An X-axis ball screw 7 is rotatably connected at the connection point between the X-axis slider 10 and the X-axis guide rail 6. Bearing seats 5 are rotatably connected to both ends of the X-axis ball screw 7. The X-axis ball screw 7 and the X-axis guide rail 6 cooperate to form a high-precision transmission structure, enabling micro-displacement control in the X-axis direction. This solves the problem of the suction needle deviating from the reaction tank due to low transmission accuracy in traditional pipetting mechanisms. The bearing seats 5 restrict the axial movement of the X-axis ball screw 7, ensuring stable screw rotation and further improving transmission accuracy.

[0038] One end of the bearing housing 5 is fixedly connected to the top of the frame 1. One end of the X-axis ball screw 7 is fixedly connected to the X-axis drive motor 3 away from the bearing housing 5. A coupling 21 is fixedly connected between the X-axis drive motor 3 and the bearing housing 5. The coupling 21 can compensate for the coaxiality deviation between the X-axis drive motor 3 and the X-axis ball screw 7, preventing screw jamming due to axis misalignment, ensuring stable power transmission, ensuring smooth movement of the X-axis slider 10, and reducing positioning deviations caused by poor power transmission.

[0039] The end of the X-axis ball screw 7 away from the X-axis drive motor 3 is fixedly connected to a position sensor 9 on one side of the bearing housing 5. The position sensor 9 is model RVI58N-011K1R61N-01024. This model supports high-speed rotation, is compatible with the drive motor shaft, and has incremental output A / B / Z phases. It can provide real-time feedback on the movement distance of the pipette arm and can be used with a PLC to achieve closed-loop control.

[0040] Position sensor 9 can collect the rotational position of X-axis ball screw 7 in real time, thereby obtaining the displacement data of X-axis slider 10, and feeding the data back to subsequent PLC controller 18 to form closed-loop control in the X-axis direction. This avoids positioning errors caused by mechanical wear in traditional open-loop control and ensures stable X-axis displacement accuracy.

[0041] The end of the X-axis drive motor 3 furthest from the coupling 21 is bolted to an L-shaped support frame 2. The end of the L-shaped support frame 2 furthest from the X-axis drive motor 3 is fixedly connected to a frame 1. The L-shaped support frame 2 can reinforce the X-axis drive motor 3 from the side, preventing displacement due to vibration during motor operation, reducing vibration transmission to the X-axis ball screw 7, preventing a decrease in transmission accuracy due to vibration, and improving the stability of the entire X-axis transmission system.

[0042] The end of the X-axis slider 10 furthest from the X-axis guide rail 6 is fixedly connected to the Y-axis mounting plate 8. The end of the Y-axis mounting plate 8 furthest from the X-axis slider 10 is fixedly connected to the Y-axis guide rail 15. The end of the Y-axis guide rail 15 furthest from the Y-axis mounting plate 8 is slidably connected to the Y-axis slider 11. The X-axis slider 10 drives the Y-axis mounting plate 8 to move. With the sliding structure of the Y-axis guide rail 15 and the Y-axis slider 11, the pipetting mechanism can move bidirectionally in the horizontal plane (XY direction). Compared with traditional single-axis movement, it can cover a larger reaction tank area. Moreover, both bidirectional transmissions rely on linear guide rails to ensure consistent positioning accuracy at all points in the plane and avoid positioning deviations in local areas.

[0043] A Y-axis ball screw 16 is rotatably connected to the Y-axis slider 11 and the Y-axis guide rail 15. Bearing seats 5 are also rotatably connected to both ends of the Y-axis ball screw 16. The bearing seats 5 and the Y-axis guide rail 15 are fitted with a clearance fit. A Y-axis mounting plate 8 is fixedly connected to one end of the bearing seat 5. The Y-axis ball screw 16 has the same structure as the X-axis ball screw 7, ensuring matching X and Y axis transmission accuracy and avoiding overall positioning deviation due to low accuracy of one axis. The clearance fit between the bearing seats 5 and the Y-axis guide rail 15 does not affect the normal operation of the guide rail and provides stable support for the ball screw, preventing screw deformation.

[0044] One end of the Y-axis ball screw 16 is fixedly connected to the Y-axis drive motor 20 away from the bearing housing 5. The surface of the Y-axis drive motor 20 is fixedly connected to the Y-axis mounting plate 8 with a motor mounting bracket 22. The motor mounting bracket 22 can tightly fix the Y-axis drive motor 20 to the Y-axis mounting plate 8. Compared with simple bolt fixing, this can further reduce motor vibration and prevent vibration from being transmitted to the Y-axis ball screw 16 through the mounting plate, ensuring stable Y-axis transmission. This forms a double anti-vibration protection with the L-shaped support frame 2 of the X-axis drive motor 3.

[0045] The end of the Y-axis ball screw 16 furthest from the Y-axis drive motor 20 is also fixedly connected to a position sensor 9 on one side of the bearing housing 5. The Y-axis position sensor 9 works in conjunction with the X-axis, synchronously feeding back the X and Y axis displacement data to the PLC controller 18, realizing full-range closed-loop control in the horizontal plane. This solves the problem of repeated position adjustments required in traditional manual liquid handling, significantly improving positioning efficiency and accuracy.

[0046] A Z-axis mounting base 12 is fixedly connected to a section of the Y-axis slider 11 away from the Y-axis guide rail 15. The Z-axis mounting base 12 is L-shaped, which allows for precise alignment of the Z-axis drive structure with the Y-axis slider 11, ensuring that the Z-axis direction is perpendicular to the XY-axis plane. This prevents Z-axis tilting from causing deviation in the suction needle angle and provides structural support for subsequent vertical liquid transfer.

[0047] A Z-axis guide rail 19 is fixedly connected to the inner side of the Z-axis mounting base 12 away from the Y-axis slider 11. A Z-axis slider 13 is slidably connected to the end of the Z-axis guide rail 19 away from the Z-axis mounting base 12. The Z-axis guide rail 19 adopts a linear guide rail structure, which, together with the Z-axis slider 13, enables smooth vertical movement, avoiding the jamming caused by uneven friction in traditional vertical transmission, ensuring smooth lifting and lowering of the aspiration needle, and preventing reagent dripping during the lifting and lowering process.

[0048] A Z-axis ball screw 23 is rotatably connected to the Z-axis slider 13 and the Z-axis guide rail 19. Bearing seats 5 are also rotatably connected to both ends of the Z-axis ball screw 23. A Z-axis mounting seat 12 is fixedly connected to one end of each bearing seat 5. The high-precision transmission of the Z-axis ball screw 23 enables micro-adjustment control of the aspiration needle, precisely adjusting the insertion depth of the needle into the reaction tank. This avoids needle contamination due to excessive depth or incomplete aspiration due to insufficient depth. Combined with the support of the bearing seats 5, this ensures long-term stability of the Z-axis transmission.

[0049] One end of the Z-axis ball screw 23, away from the bearing housing 5, is fixedly connected to the Z-axis drive motor 4. The other end of the Z-axis ball screw 23, away from the Z-axis drive motor 4, located on one side of the bearing housing 5, is also fixedly connected to a position sensor 9. The Z-axis position sensor 9, together with the X and Y axes, forms a three-axis closed-loop control system, real-time correcting the position of the aspiration needle in space. This completely eliminates the positioning errors caused by three-axis misalignment in traditional pipetting mechanisms, ensuring precise and accurate aspiration and dispensing actions.

[0050] A pipetting assembly mounting plate 14 is fixedly connected to the end of the Z-axis slider 13 away from the Z-axis guide rail 19. The surface of the pipetting assembly mounting plate 14 has pinholes that precisely match the pipetting needles, ensuring that the needles are installed vertically downwards. This avoids reagent residue or scratching of the reaction tank caused by needle tilting. At the same time, it provides a unified installation reference for multi-channel pipetting needles, ensuring consistent spacing between each needle.

[0051] The pipetting assembly mounting plate 14 is internally fixedly connected to a multi-channel aspiration needle 17. The multi-channel aspiration needle 17 is arranged in a linear row and corresponds one-to-one with the pinholes on the surface of the pipetting assembly mounting plate 14. The needle tubes are vertically downward and perpendicular to the plane of the reaction tank. The top of the needle tubes is connected to the reagent tank and peristaltic pump of the immunoblotting instrument through silicone tubing. The connection is not mechanical, but only tubing. The needle tubes are located directly above the reaction tank, away from the Z-axis mounting base 12 and the drive motor 4.

[0052] The linearly aligned multichannel aspiration needles 17 can simultaneously perform aspiration and dispensing operations on multiple reaction vessels, significantly shortening sample processing time and improving experimental efficiency compared to traditional single-channel pipetting. The non-mechanical fixing method of the silicone tubing allows for easy replacement of needles of different specifications (such as different diameters and lengths) without disassembling the mechanical structure; only the tubing and needle body need to be replaced to adapt to different reagent or reaction vessel specifications, improving system compatibility. Simultaneously, the high flexibility of the silicone tubing reduces the impact of vibration on the needles and prevents reagent leakage caused by tubing aging and damage.

[0053] A PLC controller 18 is fixedly connected to one side of the frame 1. The model of the PLC controller 18 is S7-1214CDC / DC / DCCPU1214C. It has 14 digital inputs and 10 digital outputs. It can be directly connected to the above-mentioned sensors and relays without the need for additional expansion modules. It supports high-speed counting, is compatible with encoder signal acquisition, and meets the position calculation requirements when the pipette arm moves at high speed.

[0054] The PLC controller 18 is fixedly connected to the frame 1 via four feet at the bottom. The PLC controller 18 can integrate data from the three-axis position sensor 9 and preset a fully automatic program for positioning, aspiration, and dispensing, enabling unattended operation during the liquid transfer process and reducing human error such as inconsistent dispensing volume or uneven operation intervals. The four feet ensure that the PLC controller 18 is installed stably, avoiding program disruption caused by vibration during operation and ensuring the continuity of automated operation of the equipment.

[0055] Working principle: Before the automatic pipetting mechanism of the immunoblotting instrument is put into operation, initialization preparation needs to be completed: After the PLC controller 18 on one side of the frame 1 is fixed and stabilized by the bottom feet, the signals of the position sensors 9 of each axis are detected to ensure that the X-axis slider 10, Y-axis slider 11 and Z-axis slider 13 are all at the preset origin position. At the same time, the connection status of the silicone tubing at the top of the multi-channel aspiration needle 17 to the reagent storage tank and peristaltic pump is checked to ensure that the tubing is unobstructed and leak-free.

[0056] When the PLC controller 18 receives a pipetting command, it first starts the X-axis drive motor 3. The X-axis drive motor 3 drives the X-axis ball screw 7 to rotate along the bearing seats 5 at both ends through the coupling 21. The bearing seats 5 are fixed to the frame 1 to limit the axial movement of the screw. When the X-axis ball screw 7 rotates, it drives the X-axis slider 10 to slide horizontally along the X-axis guide rail 6. At this time, the position sensor 9 at the end of the X-axis ball screw 7 collects the rotation angle of the screw in real time, converts the displacement data into an electrical signal and feeds it back to the PLC controller 18. The PLC adjusts the speed of the X-axis drive motor 3 according to the preset target position to achieve precise positioning in the X-axis direction. At the same time, the L-shaped support frame 2 on the side of the X-axis drive motor 3 can reduce motor vibration and avoid vibration transmission affecting the slider movement accuracy.

[0057] After the X-axis positioning is completed, the Y-axis drive motor 20 is started. The Y-axis drive motor 20 is fixed to the Y-axis mounting plate 8 through the motor mounting base 22. Its output end drives the Y-axis ball screw 16 to be fixed to the Y-axis mounting plate 8 along the bearing seat 5 and rotates with clearance fit with the Y-axis guide rail 15, thereby driving the Y-axis slider 11 to slide along the Y-axis guide rail 15. The position sensor 9 at the end of the Y-axis ball screw 16 synchronously feeds back the displacement data to the PLC, and calculates it together with the X-axis position data, so that the Y-axis mounting plate 8 moves with the X-axis slider 10 to drive the Y-axis assembly to adjust its position. Finally, the liquid transfer assembly fixed to the Z-axis mounting base 12 below the Y-axis slider 11 is accurately aligned with the reaction tank to be transferred in the horizontal plane.

[0058] After horizontal positioning is completed, the Z-axis drive motor 4 starts, driving the Z-axis ball screw 23 to rotate along the bearing seat 5 and the Z-axis mounting seat 12. This drives the Z-axis slider 13 to descend vertically along the Z-axis guide rail 19, which is fixed to the inside of the Z-axis mounting seat 12. The position sensor 9 at the end of the Z-axis ball screw 23 provides real-time feedback on the descent distance. The PLC controller 18 controls the Z-axis slider 13 to descend to a preset height based on the depth of the reaction tank and the liquid aspiration requirements. This allows the multi-channel aspiration needle 17, which is fixed to the bottom of the Z-axis slider 13 by the pipetting assembly mounting plate 14, to be precisely inserted into the reaction tank through the needle hole, ensuring the needle tube is vertically downward and avoiding tilting and scraping the tank wall. During liquid aspiration, the PLC controller 18 simultaneously starts the peristaltic pump. The multi-channel aspiration needle 17 is non-mechanically fixed by the silicone tubing at the top, which does not affect the Z-axis movement. Reagents are drawn from the reagent storage tank or waste liquid is extracted from the reaction tank. After liquid aspiration is completed, the Z-axis drive motor 4 rotates in the opposite direction, driving the Z-axis slider 13 to rise to a safe height.

[0059] After the aspiration needle rises, the PLC controller 18 controls the X-axis and Y-axis drive motors to work together to move the pipetting assembly horizontally to the top of the target reaction tank. Then the Z-axis slider 13 descends again, aligning the multi-channel aspiration needle 17 with the target tank. The peristaltic pump works in reverse to inject the reagent into the target tank, completing one pipetting cycle.

[0060] After a single pipetting operation is completed, the PLC controller 18 controls the X, Y, and Z axis drive motors to rotate in reverse, driving the sliders of each axis back to their initial origin positions. If continuous pipetting is required, the PLC can automatically repeat the horizontal positioning, Z-axis lifting, pipetting, and reset process according to the preset program. The linear arrangement of the multi-channel suction needles 17 can handle multiple reaction tanks simultaneously. Throughout the entire operation, the position sensors 9 of each axis continuously provide closed-loop feedback to ensure the positioning accuracy and stability of each pipetting operation, avoiding the errors and low efficiency of traditional manual pipetting.

[0061] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. An automated pipetting mechanism for an immunoblotting instrument, comprising a frame (1), characterized in that: The top two sides of the frame (1) are fixedly connected to two X-axis guide rails (6), which are linear guide rails with an I-shaped cross section. The X-axis guide rail (6) is slidably connected to an X-axis slider (10) at one end away from the frame (1). An X-axis ball screw (7) is rotatably connected at the connection between the X-axis slider (10) and the X-axis guide rail (6). Bearing seats (5) are rotatably connected at both ends of the X-axis ball screw (7). One end of the bearing seat (5) is fixedly connected to the top of the frame (1). One end of the X-axis ball screw (7) is fixedly connected to an X-axis drive motor (3) away from the bearing seat (5). A coupling (21) is fixedly connected between the X-axis drive motor (3) and the bearing seat (5). An L-shaped support frame (2) is fixedly connected to the end of the X-axis drive motor (3) away from the coupling (21) by bolts. A frame (1) is fixedly connected to the end of the L-shaped support frame (2) away from the X-axis drive motor (3). A position sensor (9) is fixedly connected to the end of the X-axis ball screw (7) away from the X-axis drive motor (3) located on one side of the bearing seat (5). The X-axis slider (10) is fixedly connected to a Y-axis mounting plate (8) at one end away from the X-axis guide rail (6), and the Y-axis mounting plate (8) is fixedly connected to a Y-axis guide rail (15) at one end away from the X-axis slider (10). The Y-axis guide rail (15) is slidably connected to a Y-axis slider (11) at one end away from the Y-axis mounting plate (8). A Y-axis ball screw (16) is rotatably connected at the connection between the Y-axis slider (11) and the Y-axis guide rail (15). A bearing seat (5) is rotatably connected at both ends of the Y-axis ball screw (16). The bearing seat (5) is clearance-fitted with both ends of the Y-axis guide rail (15) and one end is fixedly connected to the Y-axis mounting plate (8). One end of the Y-axis ball screw (16) is fixedly connected to the Y-axis drive motor (20) away from the bearing seat (5). The surface of the Y-axis drive motor (20) is fixedly connected to the motor mounting plate (8) near the Y-axis. The end of the Y-axis ball screw (16) away from the Y-axis drive motor (20) is fixedly connected to the bearing seat (5) on one side. A position sensor (9) is fixedly connected to the bearing seat (5). The Y-axis slider (11) is fixedly connected to an L-shaped Z-axis mounting base (12) at one end away from the Y-axis guide rail (15). The Z-axis guide rail (19) is fixedly connected to the inner side of the Z-axis mounting base (12) away from the Y-axis slider (11). The Z-axis slider (13) is slidably connected to the Z-axis guide rail (19) away from the Z-axis mounting base (12). A Z-axis ball screw (23) is rotatably connected at the connection between the Z-axis slider (13) and the Z-axis guide rail (19). A bearing seat (5) is rotatably connected at both ends of the Z-axis ball screw (23). One end of the bearing seat (5) is fixedly connected to the Z-axis mounting seat (12). One end of the Z-axis ball screw (23) is fixedly connected to the Z-axis drive motor (4) away from the bearing housing (5), and the other end of the Z-axis ball screw (23) away from the Z-axis drive motor (4) is fixedly connected to the position sensor (9) on the side of the bearing housing (5). The Z-axis slider (13) is fixedly connected to a pipetting assembly mounting plate (14) at one end away from the Z-axis guide rail (19). The surface of the pipetting assembly mounting plate (14) is provided with pinholes. A multi-channel aspiration needle (17) is fixedly connected inside the pipetting assembly mounting plate (14). The multi-channel aspiration needle (17) is arranged in a linear array and corresponds one-to-one with the pinholes. The needle tube of the multi-channel aspiration needle (17) is vertically downward, and the top of the needle tube is connected to the reagent storage tank and peristaltic pump of the immunoblotting instrument through silicone tubing. A PLC controller (18) is fixedly connected to one side of the frame (1), and the PLC controller (18) is fixedly connected to the frame (1) through four feet at the bottom.

2. The automated pipetting mechanism of an immunoblotting instrument according to claim 1, characterized in that: The two X-axis guide rails (6) are arranged in parallel, and the length direction of the X-axis guide rails (6) is consistent with the length direction of the horizontal mounting plane at the top of the frame (1).

3. The automated pipetting mechanism of an immunoblotting instrument according to claim 2, characterized in that: One end of the coupling (21) is fixedly connected to the output end of the X-axis drive motor (3), and the other end is fixedly connected to the end of the X-axis ball screw (7). The axis of the coupling (21) is collinear with the axis of the X-axis ball screw (7).

4. The automated pipetting mechanism of an immunoblotting instrument according to claim 3, characterized in that: The length direction of the Y-axis guide rail (15) is perpendicular to the length direction of the X-axis guide rail (6), and the Y-axis guide rail (15) is fixed to the side of the Y-axis mounting plate (8) away from the X-axis slider (10).

5. The automated pipetting mechanism of an immunoblotting instrument according to claim 4, characterized in that: The end of the multichannel aspiration needle (17) away from the pipetting assembly mounting plate (14) is located directly above the immunoblotting reaction chamber, and the needle is perpendicular to the plane of the reaction chamber.

6. The automated pipetting mechanism of an immunoblotting instrument according to claim 5, characterized in that: The L-shaped structure of the Z-axis mounting base (12) includes a horizontal section and a vertical section. The horizontal section is fixedly connected to the end of the Y-axis slider (11) away from the Y-axis guide rail (15), and the inner side of the vertical section is fixedly connected to the Z-axis guide rail (19).

7. The automated pipetting mechanism of an immunoblotting instrument according to claim 6, characterized in that: The X-axis ball screw (7), Y-axis ball screw (16), and Z-axis ball screw (23) have the same structure, and their axes are parallel to the length directions of the X-axis guide rail (6), Y-axis guide rail (15), and Z-axis guide rail (19), respectively.

8. The automated pipetting mechanism of an immunoblotting instrument according to claim 7, characterized in that: The end of the motor mounting base (22) away from the Y-axis drive motor (20) is fixedly connected to the side of the Y-axis mounting plate (8) away from the Y-axis guide rail (15), and the axis of the motor mounting base (22) is parallel to the axis of the Y-axis ball screw (16).

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