A three-degree-of-freedom pipette device based on delta robot

Abstract

The present invention relates to a three-degree-of-freedom pipette device based on a delta robot. The device drives the pipette injection head to move freely along the vertical z-axis and the horizontal x- and y-axes through the synchronous and asynchronous rotation of three lead screws. The device has a simple structure and low cost, making it suitable for miniaturized equipment and complex procedures requiring the participation of a large number of reagent wells. This greatly expands the application range of closed library preparation systems.

Description

Technical Field

[0001] The present invention relates to the technical field of library preparation equipment, and in particular to a three-degree-of-freedom pipette device based on a delta robot. Background Art

[0002] Since the 1950s, with the development of molecular genetics, people have gradually come to understand that genes are essentially segments of DNA that control biological traits and have heritable effects. While genes can faithfully replicate themselves to ensure essential biological characteristics, they can also mutate, leading to disease. Gene sequencing can quickly and accurately obtain genetic information, revealing the complexity and diversity of genomes, playing a crucial role in life science research. Similarly, gene sequencing has crucial significance and value in clinical medicine, with the mechanistic research and clinical diagnosis of many diseases increasingly relying on gene sequencing technology.

[0003] Library preparation is one of the important steps that are essential in gene sequencing. In traditional manual operations for library preparation, processes such as sample addition, warm bath reaction, purification, and elution all require human participation to complete, and the entire process is completed in a relatively open laboratory environment. The disadvantage of such an operation is that the probability of errors in human operation is very high, the results are uncontrollable, and the samples are very likely to pollute the environment, and the risk of cross-contamination between samples will also be greatly increased. Therefore, automated, closed library preparation devices and methods are a major research direction. The prior art has proposed a variety of closed, automated solutions for the library preparation process, but in the actual application of library preparation, there are still problems, especially how to provide a simple-structured, easy-to-control multi-degree-of-freedom pipette device in a limited enclosed space so that the closed library preparation device can adapt to more complex amplicon sequencing and target capture processes, which has become a technical problem that needs to be solved urgently. Summary of the Invention

[0004] To address the shortcomings of the existing technology, the present invention proposes a three-degree-of-freedom pipette device based on a delta robot. The three screws are used to drive the pipette injection head to move freely in the vertical z-axis and the horizontal x and y axes through synchronous and asynchronous rotation. It has a simple structure and low cost. It is suitable for miniaturized equipment and complex procedures requiring the participation of more reagent wells, greatly expanding the application range of closed library preparation systems.

[0005] To achieve the above objectives, the technical solutions adopted by the present invention include:

[0006] A three-degree-of-freedom pipette device based on a delta robot, characterized by comprising three rotatable screws fixedly disposed in a closed cartridge, three nut seats respectively inserted into the three screws, a horizontal positioning plate respectively connected to the three nut seats via three non-retractable connecting shafts of equal length, and a pipette injection head fixedly disposed in the center of the horizontal positioning plate;

[0007] The lead screws are vertically arranged inside the closed card box near the inner wall; the relative positions of the three lead screws inside the closed card box form an equilateral triangle; the three lead screws can rotate forward and reverse synchronously or asynchronously;

[0008] The nut seat moves vertically up and down along the lead screw by rotating the lead screw in the forward and reverse directions;

[0009] The connecting shaft includes a first universal connecting structure connected to the nut seat and a second universal connecting structure connected to the horizontal positioning plate;

[0010] The horizontal positioning plate is vertically displaced and / or moved in the horizontal plane along with the synchronous and / or asynchronous vertical displacement of the three nut seats on the lead screw, and the horizontal positioning plate always remains in a horizontal state during the vertical displacement and / or horizontal position movement;

[0011] The pipette injection head always remains perpendicular to the surface of the reagent wells of the porous reagent disk during the vertical displacement and / or horizontal position movement of the horizontal positioning disk; the pipette injection head is connected to the pump assembly arranged in the closed card box, and the pump assembly controls the liquid absorption or liquid injection operation of the reagent wells on the porous reagent disk.

[0012] Furthermore, a rotatable fixed connection position is provided at the bottom end of the screw, and a drive shaft connection position is provided at the top end; the bottom end of the screw is fixedly mounted on a fixed position protruding from the inner wall of the closed card box through the rotatable fixed connection position; the screw is connected to the motor drive shaft through the drive shaft connection position and transmits torque to drive the screw to rotate forward and reverse.

[0013] Furthermore, the nut seat is provided with a vertical slide groove on one side facing the inner wall of the closed card box, and the inner wall of the closed card box is provided with a vertical positioning bar corresponding to the position of the slide groove. The nut seat provides rotation limitation through the sliding contact between the slide groove and the positioning bar during the vertical up and down movement.

[0014] Furthermore, the first universal connection structure is a first spherical universal bearing connection structure, and the second universal connection structure is a second spherical universal bearing connection structure; the first spherical universal bearing connection structure and the second spherical universal bearing connection structure are both double-ball universal bearing connection structures fixedly connected by a horizontal rod.

[0015] Furthermore, a tension spring is connected between the horizontal rod of the first spherical universal bearing connection structure and the horizontal rod of the second spherical universal bearing connection structure; the tension spring is preloaded with tension when installed, so that the distance between the first spherical universal bearing and the second spherical universal bearing remains fixed.

[0016] Furthermore, the lead screw, nut seat, connecting shaft and horizontal positioning plate are all made of plastic.

[0017] The present invention also relates to a three-degree-of-freedom closed cartridge, characterized in that the three-degree-of-freedom pipette device based on the delta robot as described above is arranged in the closed cartridge.

[0018] Furthermore, the closed cartridge is cylindrical, and the porous reagent disc used in conjunction with the closed cartridge is disc-shaped; the surface of the reagent wells of the porous reagent disc is covered with a film that can be pierced by a pipette injection head.

[0019] Furthermore, the porous reagent disk is freely rotatable with the center of the circle as the axis.

[0020] Furthermore, the closed cartridge is provided with an openable / sealable thermal cover, and the position of the thermal cover corresponds to the reagent wells in the porous reagent disk that need to be heated or kept warm.

[0021] The beneficial effects of the present invention are:

[0022] The three-degree-of-freedom pipette device based on the delta robot described in the present invention realizes the vertical and horizontal three-degree-of-freedom displacement capability of the pipette injection head relative to the porous reagent disk through a simple screw combination structure of the delta robot, so that the pipette injection head can absorb or inject liquid into any reagent well as needed. It is particularly suitable for use in small closed cartridges, so that the closed cartridge can provide a larger number of reagent wells in a limited space, support more and more complex experimental processes, and expand the scope of application of the closed cartridge; at the same time, the overall structure of the device described in the present invention is simple and the cost is low, which can reduce the cost of using disposable closed cartridges. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of an embodiment of a three-degree-of-freedom pipette device based on a delta robot according to the present invention.

[0024] Figure 2 Schematic diagram of vertical displacement of the horizontal positioning plate of the present invention.

[0025] Figure 3 It is a schematic diagram of the horizontal displacement of the horizontal positioning plate of the present invention.

[0026] Figure 4 Schematic diagram of an embodiment of a closed card box using the device of the present invention.

[0027] Explanation of the accompanying figures: 1-screw, 11-rotatable fixed connection position, 12-drive shaft connection position, 2-nut seat, 21-slide groove, 3-connecting shaft, 31-first universal connection structure, 32-second universal connection structure, 33-tension spring, 4-horizontal positioning plate, 5-pipette injection head, 6-pump assembly, 7-fixed position, 8-porous reagent disk, 9-hot cover. DETAILED DESCRIPTION

[0028] In order to more clearly understand the content of the present invention, it will be described in detail with reference to the accompanying drawings and embodiments.

[0029] like Figure 1The figure shows a schematic diagram of a preferred embodiment of a three-degree-of-freedom pipette device based on a delta robot according to the present invention, comprising three rotatable screws 1 fixedly disposed within a closed cartridge, three nut seats 2 respectively inserted into the three screws 1, a horizontal positioning disk 4 connected to the three nut seats 2 via three non-retractable connecting shafts 3 of equal length, and a pipette injection head 5 fixedly disposed in the center of the horizontal positioning disk 4. The connections between the various components do not require the use of any screws, clips, or magnetic parts. The screws 1 are fixedly mounted to protruding fixings 7 provided on the inner wall of the closed cartridge via a rotatable fixing connection 11 provided at the bottom. The relative positions of the three screws 1 within the closed cartridge form an equilateral triangle, i.e., the connection positions of the three screws 1 are the vertices of an equilateral triangle when viewed from above. The three screws 1 are connected to the motor drive shaft via a drive shaft connection 12 provided at the top, transmitting torque to drive the motor to rotate forward or reverse synchronously or asynchronously. The nut seat 2 is moved vertically up and down along the lead screw 1 by the forward and reverse rotation of the lead screw 1 inserted therein. Preferably, the nut seat 2 is provided with a vertical slot 21 on the side facing the inner wall of the closed cartridge, and a vertical positioning bar is provided on the inner wall of the closed cartridge corresponding to the position of the slot 21. The sliding contact between the slot 21 and the positioning bar provides rotational limitation for the nut seat 2 during the vertical up and down movement. The connecting shaft 3 includes a first universal connection structure 31 connected to the nut seat 2 and a second universal connection structure 32 connected to the horizontal positioning plate 4. The horizontal positioning plate 4 is vertically displaced and / or moved in the horizontal plane along with the synchronous and / or asynchronous vertical displacement of the three nut seats 2 on the screw 1, and the horizontal positioning plate 4 always maintains a horizontal state during the vertical displacement and / or horizontal position movement; preferably, the first universal connection structure 31 is a first spherical universal bearing connection structure, and the second universal connection structure 32 is a second spherical universal bearing connection structure, and the first spherical universal bearing connection structure and the second spherical universal bearing connection structure are both double-ball universal bearing connection structures fixedly connected by a horizontal rod, wherein the double-ball structure part of the first spherical universal bearing connection structure is fixedly arranged on the nut seat 2, The double spherical structure part of the second spherical universal bearing connection structure is fixedly arranged on the horizontal positioning plate 4, and the two ends of the connecting shaft 3 body are respectively inserted into the double spherical structure parts of the first spherical universal bearing connection structure and the second spherical universal bearing connection structure, so that the connecting shaft 3 body can achieve multi-directional rotation by relying on relative sliding between the double spherical structures; and further, a tension spring 33 is connected between the horizontal rod of the first spherical universal bearing connection structure and the horizontal rod of the second spherical universal bearing connection structure, and the tension spring 33 is preloaded with tension when installed, so that the distance between the first spherical universal bearing and the second spherical universal bearing is fixed, thereby improving the accuracy of the device during operation.The pipette injection head 5 always remains perpendicular to the surface of the reagent holes of the porous reagent disk 8 during the vertical displacement and / or horizontal position movement of the horizontal positioning disk 4; the pipette injection head 5 is connected to the pump assembly 6 arranged in the closed card box, and the pump assembly 6 controls the liquid absorption or liquid injection operation of the reagent holes on the porous reagent disk 8. Preferably, the screw 1, nut seat 2, connecting shaft 3 and horizontal positioning disk 4 are all made of plastic to reduce manufacturing costs and processing difficulty. At the same time, different plastic materials can also be used to make components with different working strengths. For example, the first spherical universal bearing and the second spherical universal bearing that need to withstand sliding friction can be made of PA66 material, while the main part of the connecting shaft 3 can be made of PTFE and GF material.

[0030] like Figure 2 The figure shows the principle behind the delta robot achieving vertical displacement of the horizontal positioning plate 4. The left and right lead screws 1 rotate synchronously, causing the connected nut holders 2 to move downward a distance l, thereby achieving vertical downward displacement of the horizontal positioning plate 4. During this movement, the lengths A and B of the two connecting shafts 3 and the distance C between the two nut holders 2 remain unchanged. For ease of illustration, the figure uses a frontal perspective to illustrate the vertical displacement of the horizontal positioning plate 4 driven by two lead screws 1. However, those skilled in the art will readily understand that the delta robot achieves the same technical effect in three dimensions using three lead screws 1.

[0031] like Figure 3The figure shows a schematic diagram of the principle of the delta robot of the present invention to achieve horizontal displacement of the horizontal positioning plate 4. The asynchronous rotation of the left and right lead screws 1 causes the connected nut seat 2 to move asynchronously vertically. For example, the left lead screw 1 and the right lead screw 1 rotate in opposite directions, thereby causing the left nut seat 2 to move upward by a distance m while the right nut seat 2 moves downward by a distance n, thereby achieving leftward displacement of the horizontal positioning plate 4 in the horizontal direction (the x-axis direction in the horizontal plane). During this movement, the lengths A and B of the two connecting shafts 3 remain unchanged, but the distance between the two nut seats 2 changes from C to C'. For ease of illustration, the accompanying drawings use a frontal plane perspective to show the process of horizontal displacement (the x-axis direction in the horizontal plane) of the horizontal positioning plate 4 driven by the two lead screws 1. However, those skilled in the art can readily understand the technical effect of the delta robot achieving arbitrary displacement below the horizontal plane (the x-axis and y-axis directions in the horizontal plane) in three-dimensional space through the three lead screws 1. It can be seen from the displacement process of the horizontal positioning disk 4 in the horizontal plane that the effective displacement space of the horizontal positioning disk 4 driven by the three screws 1 is approximately a circle with the center of the equilateral triangle formed by the screws 1 as the center. Therefore, the pipette device described in the present invention is preferably used in a cylindrical closed card box to achieve the best effect, but at the same time it does not exclude the application in closed card boxes of other shapes to achieve better technical effects.

[0032] according to Figure 2 、 Figure 3 As shown in the displacement process of the horizontal positioning plate 4 in the vertical and horizontal directions, the specific position of the horizontal positioning plate 4 in the three-dimensional space is determined by the relative vertical positions of the three connected nut seats 2. Therefore, in actual use, a step-by-step displacement method of vertical displacement and horizontal displacement can be adopted, or a direct displacement method of directly positioning the height of the nut seat 2 can be adopted, that is, the horizontal positioning plate 4 can move in any direction in the three-dimensional space, and is not limited to vertical or horizontal movement.

[0033] The present invention also relates to a three-degree-of-freedom closed cartridge provided with a three-degree-of-freedom pipette device based on a delta robot as described above, such as Figure 4 The figure shows a schematic diagram of a preferred structure of a closed cartridge in the case of using the pipette device embodiment shown above, which includes, in addition to the pipette device, a cylindrical cartridge housing, a disc-shaped rotatable porous reagent disk 8, and a heat cover 9 corresponding to the reagent wells in the porous reagent disk 8 that need to be heated or kept warm.

[0034] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention are intended to be covered by the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A three-degree-of-freedom pipette device based on a delta robot, characterized in that: The device comprises three rotatable screws fixedly arranged in a closed cartridge, three nut seats respectively inserted into the three screws, a horizontal positioning plate respectively connected to the three nut seats via three non-retractable connecting shafts of equal length, and a pipette injection head fixedly arranged in the center of the horizontal positioning plate; The lead screws are vertically arranged inside the closed card box near the inner wall; the relative positions of the three lead screws inside the closed card box form an equilateral triangle; the three lead screws can rotate forward and reverse synchronously or asynchronously; The nut seat moves vertically up and down along the lead screw by rotating the lead screw in the forward and reverse directions; The connecting shaft includes a first universal connecting structure connected to the nut seat and a second universal connecting structure connected to the horizontal positioning plate; The horizontal positioning plate is vertically displaced and / or moved in the horizontal plane along with the synchronous and / or asynchronous vertical displacement of the three nut seats on the lead screw, and the horizontal positioning plate always remains in a horizontal state during the vertical displacement and / or horizontal position movement; The pipette injection head always remains perpendicular to the surface of the reagent wells of the porous reagent disk during the vertical displacement and / or horizontal position movement of the horizontal positioning disk; the pipette injection head is connected to a pump assembly disposed in the closed cartridge, and is controlled by the pump assembly to perform liquid aspiration or liquid injection operations on the reagent wells on the porous reagent disk; The first universal connection structure is a first spherical universal bearing connection structure, and the second universal connection structure is a second spherical universal bearing connection structure; the first spherical universal bearing connection structure and the second spherical universal bearing connection structure are both double-ball universal bearing connection structures fixedly connected by a horizontal rod; A tension spring is connected between the horizontal rod of the first spherical universal bearing connection structure and the horizontal rod of the second spherical universal bearing connection structure; the tension spring is preloaded with tension when installed, so that the distance between the first spherical universal bearing and the second spherical universal bearing remains unchanged; The two ends of the connecting shaft body are respectively clamped into the double spherical structure parts of the first spherical universal bearing connection structure and the second spherical universal bearing connection structure; The nut seat is provided with a vertical slide groove on one side facing the inner wall of the closed card box, and the inner wall of the closed card box is provided with a vertical positioning bar protruding corresponding to the position of the slide groove. The nut seat provides rotation limitation through the sliding contact between the slide groove and the positioning bar during the vertical up and down movement.

2. The device according to claim 1, wherein The bottom end of the screw is provided with a rotatable fixed connection position, and the top end is provided with a drive shaft connection position; the bottom end of the screw is fixedly mounted on a fixed position protruding from the inner wall of the closed card box through the rotatable fixed connection position; the screw is connected to the motor drive shaft through the drive shaft connection position and transmits torque to drive the screw to rotate forward and reverse.

3. The device according to claim 1, wherein The lead screw, nut seat, connecting shaft and horizontal positioning plate are all made of plastic.

4. A three-degree-of-freedom closed card box, characterized in that: The closed cartridge is provided with a delta robot-based three-degree-of-freedom pipette device as described in any one of claims 1 to 3.

5. The closed card box according to claim 4, characterized in that The closed cartridge is cylindrical, and the porous reagent disc used in conjunction with the closed cartridge is disc-shaped; the surface of the reagent holes of the porous reagent disc is covered with a film that can be pierced by the injection head of the pipette.

6. The closed cartridge according to claim 5, wherein: The porous reagent disk is freely rotatable with the center of the circle as the axis.

7. The closed cartridge according to claim 6, wherein: The closed cartridge is further provided with an openable / sealable thermal cover, the position of the thermal cover corresponding to the reagent wells in the porous reagent disk that need to be heated or kept warm.

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