A powder adding device and pretreatment equipment for sample testing

Abstract

This invention discloses a powder feeding device and pretreatment equipment for sample testing, relating to the technical field of sample processing. It includes a workbench with a first powder feeding seat and a second powder feeding seat capable of horizontal reciprocating motion along a first direction. Test tube racks are mounted on the first and second powder feeding seats respectively. At least one of the first and second powder feeding seats is capable of rotating along a vertical axis. A feeding assembly is mounted above the workbench, positioned above the movement trajectories of the first and second powder feeding seats. The feeding assembly includes multiple material cylinders, each with a discharge port at its lower end. Each material cylinder contains a feeding mechanism, and a driving mechanism is located above the cylinder. The driving mechanism has multiple downward-facing and rotatable driving heads. At least one of the feeding assembly and the driving mechanism is capable of lifting and lowering, allowing the driving head to be detachably connected vertically to the driving part at the top of the feeding mechanism. The driving head can rotate to drive the feeding mechanism, thereby quantitatively outputting the material from the material cylinder.

Description

Technical Field

[0001] This invention relates to the technical field of sample processing, and more specifically, to a powder adding device and pretreatment equipment for sample testing. Background Technology

[0002] In the field of sample residue detection, fully automated pretreatment equipment typically integrates laboratory instrument modules (phase shifting, powder addition, vortexing, shaking, centrifugation, sample concentration, filtration, cooling, etc.) into the same device. Through a moving gripping mechanism, the sample is transferred in series between different instrument modules according to a predetermined process.

[0003] In the pretreatment standards for pesticide and veterinary drug residues, the extraction and purification of samples are typically accomplished using salt packs and purification packs. For example, in the national standard GB23200.113-2018 "Determination of Residues of 208 Pesticides and Their Metabolites in Plant-Derived Foods by Gas Chromatography-Mass Spectrometry," for vegetable pretreatment, the extraction step requires the addition of 4g magnesium sulfate, 1g sodium chloride, 1g sodium citrate, and 0.5g disodium hydrogen citrate to the sample. For grain pretreatment, 6g magnesium sulfate and 1.5g sodium acetate are required. It is evident that the types of salts required for extraction and purification differ depending on the sample type during the pretreatment of pesticide and veterinary drug residues.

[0004] In existing technologies, mixed salt addition or pre-packaged salt packets are typically used to address the processing needs of different samples. The former requires machine shutdown for cleaning and salt replacement when switching sample types, leading to interruptions in unattended processes; while the latter avoids material changes mid-process, pre-packaging salt packets increases user costs and is limited by the types of salt packets available, making it difficult to flexibly handle diverse experimental scenarios.

[0005] Furthermore, in the powder addition process for sample testing, especially when handling large batches of samples, it is usually necessary to screw on the end caps of the test tubes to seal them and prevent the powder from absorbing moisture or causing contamination. In existing automated equipment, if powder addition is required, a robotic arm and a dedicated container must be added. The robotic arm grasps the end cap, screws it open, and transfers the powder; after adding the powder, it is aligned and screwed closed again. This process not only increases the complexity of equipment control but also occupies a significant amount of internal space due to the robotic arm and container, resulting in a bulky overall structure and hindering the miniaturization and efficient integration of the equipment. Summary of the Invention

[0006] The purpose of this invention is to provide a powder-adding device and a pretreatment equipment for sample testing, so as to at least solve one of the above-mentioned technical problems.

[0007] To achieve the objective of this invention, the technical solution adopted is a powder dispensing device for sample testing, comprising a worktable, on which are provided a first powder dispensing seat and a second powder dispensing seat capable of horizontal reciprocating motion along a first direction, respectively. Test tube racks are respectively mounted on the first and second powder dispensing seats, and at least one of the first and second powder dispensing seats is capable of rotating along a vertical axis. A feeding assembly is mounted above the worktable, positioned above the movement trajectories of the first and second powder dispensing seats. The feeding assembly includes multiple material cylinders, each with a discharge port at its lower end. Each material cylinder is equipped with a feeding mechanism, and a driving mechanism is located above the cylinder. The driving mechanism has multiple downward-facing and rotatable driving heads. At least one of the feeding assembly and the driving mechanism is capable of lifting and lowering, so that the driving head is vertically detachably connected to the driving part at the top of the feeding mechanism. The driving head can rotate to drive the feeding mechanism, thereby quantitatively discharging the material from the material cylinder.

[0008] Furthermore, the first powder filling station and / or the second powder filling station include a turntable, a support and a weighing module arranged sequentially from top to bottom. The weighing module is connected to a linear drive assembly on the workbench, the support is fixed to the weighing module, the turntable is rotatably connected to the support, and a test tube rack is fixed above the turntable. The test tube rack is provided with multiple test tube ports.

[0009] Furthermore, the material cylinder includes a detachably connected cylinder body and a top cover, and the feeding mechanism includes a rotating shaft rotatably mounted on the top cover, the lower end of the rotating shaft extending to the discharge port of the cylinder body, and the lower end of the rotating shaft having a screw conveying section.

[0010] Furthermore, the drive unit is a socket located at the top of the rotating shaft, and the drive mechanism includes multiple motors. The output shaft of the motor is equipped with a drive head, which coincides with the rotation axis of the rotating shaft.

[0011] Furthermore, a top plate is fixed above the workbench by multiple guide rods, a drive mechanism is fixed above the top plate by support rods, a lifting plate is installed below the top plate, multiple material cylinders are installed on the lifting plate, and multiple through holes are provided on the top plate to accommodate the material cylinders passing through or detaching from the top.

[0012] Furthermore, the material cylinder is rotatably connected to the lifting plate, and the lifting plate is equipped with a first locking mechanism to lock the material cylinder. The material cylinder is equipped with a second locking mechanism to lock the feeding mechanism. The lower end of the material cylinder forms a discharge section with a non-circular cross-section. The discharge section has a discharge port, and test tubes are installed on the test tube rack. An end cap is threaded to the upper end of each test tube, and the end cap has a drive port that can be inserted into the discharge section. A sealing block is installed below the drive port to accommodate the lower end of the discharge section.

[0013] Furthermore, a guide is provided between the test tube rack and the test tubes, which is inserted vertically to restrict the rotation of the test tubes relative to the test tube inlet.

[0014] Furthermore, the first locking element is a limiting frame located at the lower end of the drive mechanism. The limiting frame can be raised and lowered relative to the drive mechanism. The limiting frame has multiple limiting rods, and the top of the material cylinder is provided with a limiting hole for inserting into the limiting rods.

[0015] Furthermore, the second locking element includes a locking plate rotatably mounted on the top wall of the material cylinder, with a torsion spring and a magnetic attraction assembly between the locking plate and the material cylinder. The torsion spring is used to drive the locking plate away from the locking notch at the top of the feeding mechanism, and the magnetic attraction assembly is used to drive the locking plate to stop against the notch.

[0016] One or more embodiments of this patent also provide a sample pretreatment device for testing, including a frame on which the above-described powder addition device for sample testing is mounted.

[0017] The beneficial effects of one or more of the above technical solutions are: (1) In this scheme, the first powder feeding seat and the second powder feeding seat can move horizontally back and forth along the first direction, and can move alternately to the bottom of the feeding component to complete the powder feeding, realize the continuous processing of batch samples, avoid the time loss of waiting for the material to be fed by a single powder feeding seat, and improve the powder feeding efficiency; at least one powder feeding seat can rotate along the vertical axis, drive the test tube rack to rotate, so that any test tube can be aligned with the material cylinders of different columns above by rotation, increasing the feeding type of test tubes on the rotating test tube rack.

[0018] The feeding assembly is equipped with multiple material cylinders, which can be used to load different types of salts or powdered materials. There is no need for pre-packaging salt bags or stopping the machine for cleaning and material replacement. Based on the testing requirements of different samples, the corresponding material cylinder's feeding mechanism is driven by a drive mechanism to achieve quantitative output of various materials. At least one of the drive mechanism and the feeding assembly is height-adjustable, allowing for detachable connection between the drive head and the feeding mechanism's drive unit. This ensures drive stability, facilitates the inspection, maintenance, and replenishment of the material cylinders, and prevents interference between the drive head and the feeding mechanism when not in operation, thus improving the reliability of the device.

[0019] (2) The powder feeding seat adopts a layered structure of turntable, support and weighing module. The weighing module can detect the weight of the test tube rack in real time and feed it back to the control system, thereby indicating whether the powder feeding amount is accurate, avoiding detection errors caused by too much or too little material, especially suitable for scenarios with strict requirements on salt addition in pesticide and veterinary drug residue testing; the linear drive component drives the weighing module and the entire powder feeding seat to move, ensuring the stability of the horizontal reciprocating motion of the powder feeding seat and avoiding material spillage or test tube tipping during the movement. Multiple test tube slots on the test tube rack can load multiple test tubes at the same time, realizing simultaneous powder feeding of multiple test tubes, further improving batch processing efficiency and adapting to the needs of large-scale sample testing.

[0020] (3) The cylinder adopts a structure in which the cylinder body and the top cover can be detachably connected, which facilitates the cleaning of the cylinder body, the replenishment of materials and the maintenance of the feeding mechanism, and avoids cross-contamination caused by material residue; the screw conveyor at the lower end of the rotating shaft can uniformly and stably convey the powder material in the cylinder to the discharge port, avoiding the powder from absorbing moisture and clumping, which can cause feeding blockage. At the same time, the screw conveyor can control the feeding amount by controlling the rotating shaft speed, thereby improving the accuracy of quantitative output.

[0021] (4) The drive unit is set as the socket at the top of the rotating shaft. The drive head is adapted to the socket and the drive head coincides with the rotation axis of the rotating shaft to avoid the rotating shaft jamming caused by the offset of power transmission and improve the running stability of the feeding mechanism. The drive mechanism adopts multiple motors, each motor corresponds to a drive head, which can realize the independent drive of multiple material cylinder feeding mechanisms. It can control the feeding of a certain material individually, and can also realize the synchronous feeding of multiple materials to meet the powdering needs of different samples.

[0022] (5) The top plate is fixed above the workbench by a guide rod. The guide rod can ensure the installation stability of the top plate and provide guidance for the lifting plate to avoid deviation or jamming during the lifting process. The drive mechanism is fixed above the top plate, and the lifting plate is installed below the top plate and loaded with the material cylinder, reducing the space occupied by the device. The through hole on the top plate can accommodate the upper end of the material cylinder to pass through or detach. With the lifting of the lifting plate, it can realize the docking of the material cylinder and the drive mechanism (the upper end of the material cylinder passes through the through hole and docks with the drive head) and the separation of the material cylinder and the drive mechanism (the upper end of the material cylinder detaches from the through hole, which is convenient for disassembly, replenishment or maintenance of the material cylinder). At the same time, it improves the accuracy of docking between the drive mechanism and the unloading mechanism and avoids failure caused by docking deviation.

[0023] (6) The material cylinder is rotatably connected to the lifting plate. With the first locking mechanism, the rotation and locking of the material cylinder can be flexibly realized, avoiding the discharge deviation caused by the rotation of the material cylinder during the feeding and powdering process, as well as the situation where the feeding mechanism and the material cylinder rotate synchronously and cannot discharge. The second locking mechanism can lock the feeding mechanism in the non-feeding state to prevent the feeding mechanism from rotating itself and affecting the rotation of the material cylinder, so that the discharge part at the lower end of the material cylinder can be used to insert the top cap of the test tube. The rotation of the material cylinder can be used to open the end cap and expose the opening at the top of the test tube. In addition, the discharge part at the lower end of the material cylinder can pass through the seal on the end cap drive port to avoid the end cap affecting the discharge of the discharge part. This eliminates the need for additional configuration of a robot and a special bin, simplifies the equipment structure, and reduces the space occupied by the equipment.

[0024] (7) The vertical insertion guide between the test tube rack and the test tube can restrict the rotation of the test tube relative to the test tube insertion port, and prevent the test tube from rotating synchronously with the end cap when the material cylinder drives the end cap to be screwed, which would cause the test tube to tip over, the material to spill or the end cap to not be screwed in place; at the same time, the guide can realize the quick positioning and insertion of the test tube, which is convenient for loading and unloading the test tube, improving the operating efficiency, while ensuring the consistency of the installation of multiple test tubes, ensuring the accurate docking of the material cylinder discharge part with the end cap of each test tube, and improving the stability and reliability of batch powder addition.

[0025] (8) The first locking component is set as the limit frame at the lower end of the drive mechanism. The limit frame can be raised and lowered relative to the drive mechanism. The limit rod is inserted into the limit hole at the top of the material cylinder, which can quickly lock and unlock the material cylinder. When the material cylinder is connected to the drive head, the limit frame descends and the limit rod is inserted into the limit hole to lock the material cylinder, preventing the material cylinder from rotating synchronously when driven by the drive head to feed, thus ensuring the stable operation of the feeding mechanism. When it is necessary to disassemble the material cylinder, the limit frame rises and the limit rod disengages from the limit hole to unlock the material cylinder, making the operation convenient.

[0026] (9) The locking plate cooperates with the magnetic attraction component through the torsion spring. In the non-working state, the torsion spring drives the locking plate away from the locking notch of the feeding mechanism, and the magnetic attraction component drives the locking plate to stop the notch, thereby locking the feeding mechanism and preventing material leakage caused by the feeding mechanism's malfunction. When the driving mechanism is connected to the feeding mechanism, the driving head pushes the locking plate to overcome the attraction of the magnetic attraction component, and the torsion spring drives the locking plate to disengage from the locking notch, thereby unlocking the feeding mechanism. The driving head can then drive the feeding mechanism to operate normally. No manual operation is required for locking and unlocking, thus achieving automated control.

[0027] (10) The powder adding device can be seamlessly connected with other modules of the pretreatment equipment such as phase shifting, vortexing, and oscillation to realize the full automation of sample pretreatment process without manual intervention in the powder adding process, thereby improving the automation level and working efficiency of the pretreatment equipment. Attached Figure Description

[0028] The accompanying drawings illustrate exemplary embodiments of the invention and, together with the description thereof, serve to explain the principles of the invention. These drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification.

[0029] Figure 1 This is a structural diagram of the powder-adding device for sample testing provided in Embodiment 1 of the present invention; Figure 2 This is a structural diagram of the linear powder feeding seat in Embodiment 1 of the present invention; Figure 3 This is a structural diagram of the rotating linear powder feeding seat in Embodiment 1 of the present invention; Figure 4 This is a transmission structure diagram of the turntable and drive motor 2 in Embodiment 1 of the present invention; Figure 5 This is a structural diagram of the drive module in Embodiment 1 of the present invention; Figure 6 This is a cross-sectional view of the powder-adding cylinder in Embodiment 1 of the present invention; Figure 7 This is a schematic diagram of the first locking mechanism installed below the driving mechanism in Embodiment 2 of the present invention; Figure 8 This is a schematic diagram of the cooperation between the material cylinder and the first locking mechanism and the second locking mechanism in Embodiment 2 of the present invention.

[0030] Figure 9 yes Figure 8 Enlarged structural diagram of section A; Figure 10 This is a partial cross-sectional view of the test tube in Embodiment 2 of the present invention; Figure 11 This is a schematic diagram of the fit between the discharge section and the end cap of the test tube in Embodiment 2 of the present invention.

[0031] The attached diagram shows the following components: 1. Workbench; 2. Linear drive assembly; 3. Weighing module; 4. Linear powder feeding seat; 5. Rotary powder feeding seat; 6. Test tube rack; 7. Guide rod; 8. Lifting plate; 9. Material cylinder; 10. Guide sleeve; 11. Feeding mechanism; 12. Drive mechanism; 51. Support; 52. Second drive motor; 53. Driving pulley; 54. Driven pulley; 55. Belt; 56. Turntable; 61. Test tube inlet; 91. Cylinder; 92. Top cover; 111. Rotating shaft; 112. Drive unit; 113. Stirring rod; 114. Screw conveyor unit; 121. Top plate; 122. Upper fixed plate; 123. First drive motor; 124. Drive head; 126. Lead screw; 127. Nut; 128. Shell. 13. Electric push rod; 14. Limiting frame; 15. Limiting rod; 17. Limiting hole; 18. Test tube; 19. End cap; 20. Drive port; 21. Sealing block; 22. Discharge section; 24. Limiting port; 25. Groove; 26. Electromagnetic suction assembly; 27. Locking plate; 28. Fixing plate Detailed Implementation The present invention 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 invention. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present invention are shown in the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0032] Example 1 like Figures 1-6As shown, the present invention provides a powder-adding device for sample testing, including a workbench 1. The workbench 1 is provided with a first powder-adding seat and a second powder-adding seat that can reciprocate horizontally along a first direction (in this embodiment, the first direction is the left and right direction shown in the figure). Test tube racks 6 are respectively installed on the first powder-adding seat and the second powder-adding seat. At least one of the first powder-adding seat and the second powder-adding seat can rotate along a vertical axis. In this embodiment, the first powder-adding seat is a linear powder-adding seat 4, which can only reciprocate along the first direction. The second powder-adding seat is a rotating powder-adding seat 5, which can both reciprocate along the first direction as a whole and rotate around its own vertical central axis. The working mode can be flexibly switched according to the actual processing needs.

[0033] A feeding assembly is installed above the workbench 1. The feeding assembly is positioned above the movement trajectories of the first and second powder feeding seats, ensuring that both powder feeding seats can align with the corresponding material cylinders and complete the powder feeding operation when they move to the bottom of the feeding assembly. The feeding assembly includes multiple material cylinders 9 (in this embodiment, 11 material cylinders 9 are provided, which can be flexibly increased or decreased according to the type and quantity of materials, of which 5 material cylinders are above the movement trajectory of the linear powder feeding seat and 6 material cylinders are above the rotary powder feeding seat). The lower end of the material cylinder 9 has a discharge port (the discharge port diameter is 3-5mm, which can be adjusted according to the powder particle size). Each material cylinder 9 is provided with a feeding mechanism 11, and a driving mechanism 12 is provided above the material cylinder 9. The driving mechanism 12 has multiple downward-facing and rotatable driving heads 124 (the number of driving heads 124 corresponds one-to-one with the number of material cylinders 9). At least one of the feeding assembly and the driving mechanism 12 can be raised and lowered. In this embodiment, the feeding assembly is raised and lowered so that the driving head 124 and the driving part 112 at the top of the feeding mechanism 11 can be detachably connected vertically. The drive head 124 can rotate to drive the feeding mechanism 11 to operate, thereby quantitatively outputting the material in the material cylinder 9 to meet the powdering requirements for pesticide residue and veterinary residue testing.

[0034] In this embodiment, the first powder dispensing seat and / or the second powder dispensing seat include a turntable 56, a support 51, and a weighing module 3 arranged sequentially from top to bottom. The weighing module 3 uses a high-precision electronic weighing sensor and is connected to a linear drive assembly 2 on the workbench 1. The linear drive assembly 2 uses a linear motor. The support 51 is connected to the weighing module 3 to ensure a stable connection. The turntable 56 and the support 51 are rotatably connected by bearings to ensure smooth rotation of the turntable 56. A test tube rack 6 is fixed above the turntable 56 by positioning pins and bolts. The test tube rack 6 has multiple test tube slots 61. As a specific structural form, the test tube rack on the linear powder dispensing seat 4 has 5 test tube slots, which are arranged in a row along the first direction. The rotating powder dispensing seat has two types of test tube slots (corresponding to test tubes of different diameters), with 4 slots of each type, which are staggered and evenly distributed along the circumferential axis of rotation.

[0035] Specifically, a second drive motor is installed on the support 51. The output shaft of the second drive motor 52 is coaxially fixed with the drive pulley 53. The turntable 56 is coaxially fixed with the driven pulley 54. The driven pulley 54 and the drive pulley 53 are connected by a synchronous belt 55. The rotation speed of the turntable 56 is adjustable and can be adjusted according to the powder addition requirements.

[0036] In this embodiment, the material cylinder 9 includes a detachably connected cylinder body 91 and a top cover 92. The detachable connection between the cylinder body 91 and the top cover 92 facilitates disassembly for cleaning and material replenishment. The feeding mechanism 11 includes a rotating shaft 111 rotatably mounted on the top cover 92 via bearings. The lower end of the rotating shaft 111 extends to the discharge port of the cylinder body 91, and the lower end of the rotating shaft 111 has a spiral conveying part 114. A stirring rod 113 is also provided in the middle of the rotating shaft 111, which can stir the powder material in the material cylinder 9 when the rotating shaft 111 rotates, preventing the powder from absorbing moisture and clumping, and ensuring smooth feeding. Specifically, a limiting block and a groove are provided between the top cover 92 and the cylinder body 91 to prevent them from rotating relative to each other.

[0037] In this embodiment, the drive unit 112 is a socket (the socket is Y-shaped and 10mm deep) located on the top of the rotating shaft 111. The drive mechanism 12 includes multiple servo motors. The output shaft of the motor is equipped with a drive head 124 through a flexible coupling. The drive head 124 coincides with the rotation axis of the rotating shaft 111. The shape of the drive head 124 is adapted to the socket to ensure that the drive head 124 can stably transmit power after being inserted into the socket, and to avoid the rotating shaft 111 from jamming due to power transmission deviation.

[0038] In this embodiment, a top plate 121 is fixed above the workbench 1 by four guide rods 7 (the guide rods 7 are circular optical shafts). The guide rods 7 are fixed to the workbench 1 and the top plate 121 by bolts to ensure stable installation. A drive mechanism 12 is fixed above the top plate 121 by four support rods. A lifting plate 8 is installed below the top plate 121. Multiple material cylinders 9 are installed on the lifting plate 8 by bearing seats. The top plate 121 is provided with multiple through holes for the upper end of the material cylinders 9 to pass through or detach, so that the upper end of the material cylinders 9 can pass through the through holes and dock with the drive head 124.

[0039] Specifically, multiple guide holes are provided on the lifting plate 8 to accommodate the guide rods 7. A guide sleeve 10 (with an inner diameter adapted to the guide rod 7) is fixed at each guide hole, coaxial with the lifting plate 8, to better guide the lifting plate 8 and guide rods 7, reducing friction and offset during lifting. To achieve the lifting of the lifting plate 8, a lead screw 126 is provided on the lifting plate 8. The lead screw 126 passes through a nut on the lifting plate 8. A rotary motor is provided at the upper end of the drive mechanism 12 to drive the lead screw 126. The rotary motor is connected to the lead screw 126 via a coupling, allowing precise control of the lifting height of the lifting plate 8. To ensure smooth rotation of the lead screw 126, another matching nut 127 is provided on the top plate 121, which is rotatably connected to the top plate 121 via a bearing.

[0040] The drive assembly includes a housing 128, inside which is an upper fixing plate 122. The upper fixing plate 122 is located at the bottom of the housing 128 and is fixed to the top of the support rod. Multiple first drive motors 123 (i.e., the aforementioned servo motors) are mounted on the support plate by bolts. The output shaft of the first drive motor 123 extends downward and is connected to the drive head 124.

[0041] This embodiment also provides a sample pretreatment device, including a frame made of aluminum alloy, which is lightweight and stable. The aforementioned powder feeding device for sample testing is installed on the frame. The powder feeding device is fixedly connected to the frame by bolts and can be seamlessly connected with other modules of the pretreatment device such as phase shifting, vortexing, oscillation, and centrifugation to realize full automation of the sample pretreatment process.

[0042] Working principle: The lifting plate adopts front and rear partitions to form two independent material cylinders. The linear powder feeding seat and the rotary powder feeding seat each correspond to their own dedicated material cylinder group. The movement area and the feeding area are completely isolated. The two workstations operate independently and are adapted to synchronous diversion powder feeding operations for different formula samples.

[0043] The two powder feeding stations are driven by independent linear drive components, and only perform horizontal reciprocating motion within the area below their respective material cylinder groups. The linear powder feeding station only aligns with the front material cylinder group to complete the feeding, while the rotary powder feeding station only aligns with the rear material cylinder group to complete the feeding. The movement trajectory and feeding area are isolated, and they can operate independently at the same time or in staggered shifts, avoiding station interference and greatly improving the throughput of batch sample processing.

[0044] Multiple sets of material cylinders can store different types of salt purification reagents such as magnesium sulfate, sodium chloride, sodium citrate, and sodium acetate. The feeding assembly is driven vertically by a lifting plate, guide rod, and lead screw. When the lifting plate rises, the top of each material cylinder simultaneously connects to the independent drive head of the upper drive mechanism, realizing a detachable vertical insertion connection between the feeding mechanism and the drive motor. During non-feeding phases, the lifting plate moves downwards and separates, facilitating individual disassembly, replenishment, cleaning, and maintenance of each material cylinder.

[0045] The drive mechanism uses a one-to-one correspondence between servo motors and drive heads, allowing for independent start / stop and speed control of the front and rear sets of material cylinders. During the feeding operation, the drive head drives the rotating shaft to rotate synchronously, and the stirring rod in the middle of the shaft continuously agitates the powder inside the cylinder, breaking up powder agglomeration. The lower screw conveyor section uses a fixed-distance screw pushing method, relying on the number of motor rotations to achieve quantitative and stable feeding.

[0046] In the rotary powder dispensing station, the turntable and the upper test tube rack are driven by synchronous belt drive to rotate and index around the vertical axis. The test tube rack is evenly distributed with test tube slots of various specifications. Different test tubes can be switched by rotating to align different tubes with the dedicated material cylinder group on the back, which can meet the needs of adding multiple reagents to a single sample in sequence. The linear powder dispensing station has no rotation and only performs linear translation, which is suitable for rapid and continuous powder dispensing of different formulas and large batches of samples.

[0047] Two powder feeding stations independently collect the weight of the test tube assembly and the amount of material added at each station in real time, forming an independent weighing closed-loop control system. This system is used to comprehensively evaluate whether the material feeding of all feeding components above the powder feeding station meets the requirements. However, when multiple cylinders and test tubes are fed simultaneously, the overall weight is found to be inconsistent. This can be addressed by adding material to each cylinder one by one and shutting off the other cylinders to troubleshoot which cylinder is experiencing a feeding failure or deviation.

[0048] This powder addition device is integrated inside the pretreatment equipment frame and can be linked sequentially with functional modules such as pipetting, shaking, centrifugation, and filtration. Relying on the dual-zone independent powder addition structure, it can achieve parallel pretreatment of two types of samples, with fully automated and unattended operation.

[0049] Example 2 like Figures 7-11 As shown, this embodiment optimizes the material cylinder 9, the test tube sealing structure, and the locking mechanism based on embodiment 1. The specific structure is as follows: In this embodiment, the material cylinder 9 and the lifting plate 8 are rotatably connected by bearings. The lifting plate 8 is provided with a first locking mechanism to lock the material cylinder 9, and the material cylinder 9 is provided with a second locking mechanism to lock the feeding mechanism 11. The lower end of the material cylinder 9 forms a discharge section with a square cross-section. The discharge section has a discharge port, which is the same as in Embodiment 1. Test tubes are installed on the test tube rack 6. The upper end of the test tube is threadedly connected to an end cap. The end cap has a drive port that can be inserted into the discharge section (the shape of the drive port is adapted to the discharge section). A sealing block is installed below the drive port to accommodate the lower end of the discharge section. The sealing block is made of silicone material and has good elasticity and sealing performance. The sealing block includes four sealing parts, which form a cross-shaped sealing gap between the four sealing parts. When the discharge section does not pass through, the elasticity between the multiple sealing parts is sufficient to seal the gap, reduce moisture entering the test tube, and prevent the powder from absorbing moisture. When the discharge section passes through, the sealing parts can tightly fit the outer wall of the discharge section to fix it and prevent the end cap from falling off.

[0050] To further prevent the end cap from falling off, the discharge section and the end cap are magnetically attracted together. Specifically, a permanent magnet is embedded at the lower end of the discharge section, and an iron sheet is embedded in the inner wall of the end cap drive port.

[0051] In this embodiment, a guide is provided between the test tube rack 6 and the test tube for vertical insertion. The guide consists of a vertical guide groove on the inner wall of the test tube inlet 61 and a vertical guide protrusion on the outer wall of the test tube. The guide groove and the guide protrusion are adapted to restrict the rotation of the test tube relative to the test tube inlet 61, so as to prevent the test tube from rotating synchronously with the end cap when the material cylinder 9 drives the end cap to be screwed, which would cause the test tube to tip over, spill material, or the end cap to not be screwed in place. At the same time, the guide can realize the rapid positioning and insertion of the test tube.

[0052] In this embodiment, the first locking element is a limiting frame located at the lower end of the drive mechanism 12. The limiting frame is formed by bending steel plate and can be raised and lowered relative to the drive mechanism 12. The limiting frame has multiple limiting rods (the number of limiting rods corresponds one-to-one with the number of material cylinders 9). The top of the material cylinder 9 is provided with a limiting hole for inserting the limiting rod. The raising and lowering of the limiting frame is driven by a small cylinder. The cylinder is fixed on the housing 128 of the drive mechanism 12, and the cylinder piston rod is fixedly connected to the limiting frame, which can realize the rapid raising and lowering of the limiting frame. When the material cylinder 9 is connected to the drive head 124, the cylinder drives the limiting frame to descend, and the limiting rod inserts into the limiting hole to lock the material cylinder 9. When it is necessary to disassemble the material cylinder 9 or to use the material cylinder 9 to drive the upper end cap of the test tube to open, the cylinder drives the limiting frame to rise, the limiting rod disengages from the limiting hole, and the material cylinder 9 is unlocked, making the operation convenient.

[0053] In this embodiment, the second locking element includes a locking plate rotatably mounted on the groove of the top wall of the barrel. A torsion spring and an electromagnetic attraction assembly are provided between the locking plate and the barrel. The torsion spring drives the locking plate to extend to the groove, and the electromagnetic attraction assembly drives the locking plate to retract to the notch. A radially extending fixing plate is fixed on the driving part, and a limiting hole for accommodating the locking plate is provided on the lower surface of the fixing plate. When it is necessary to use the rotation of the barrel to open the upper cap of the test tube, the feeding mechanism first rotates in the opposite direction, so that the fixing rod moves above the locking plate, the limiting hole aligns with the locking plate, and the magnetic attraction assembly drives the locking plate to pop up upward to embed into the limiting hole, locking the feeding mechanism 11 and preventing the feeding mechanism 11 from rotating and affecting the power transmission to the barrel. When the feeding mechanism needs to feed, the magnetic attraction assembly is de-energized, the torsion spring drives the locking plate to retract to the groove, unlocking the feeding mechanism 11, and the driving head 124 can drive the feeding mechanism 11 to operate normally without manual operation, realizing automated control.

[0054] Working principle: The working principle of this embodiment is basically the same as that of embodiment 1. The difference is that when it is necessary to use the material cylinder to open and close the end cap, all test tubes are first moved to the bottom of the material cylinder assembly so that each test tube with the end cap to be opened has a corresponding material cylinder above it.

[0055] The feeding mechanism inside the barrel above the test tube rotates in the reverse direction (without discharging material), causing the drive unit and the fixing rod to rotate directly above the slot and the locking plate. At this point, the locking plate pops out to lock the feeding mechanism and the barrel. The entire lifting plate descends, causing the discharge part of the barrel to pass downwards into the end cap's inlet, and the lower end of the discharge part passes through the sealing block to prevent the end cap from affecting subsequent feeding.

[0056] The first locking mechanism on the barrel unlocks, causing the barrel to rotate and rise during rotation, facilitating the detachment of the end caps from the test tubes. This continues until all end caps detach simultaneously from their corresponding test tubes. The top openings of the test tubes are exposed, and the powder feeding seat moves to below different barrels via linear or rotary motion.

[0057] Then the second locking mechanism unlocks, and the first locking mechanism locks. Different quantities of powder are added to the test tubes using the feeding assembly and different feeding cylinders. It is important to note that the feeding assembly needs to be rotated forward a certain angle first to compensate for the stroke error caused by the reverse rotation of the feeding mechanism.

[0058] Those skilled in the art should understand that the above embodiments are merely for illustrating the present invention and are not intended to limit the scope of the invention. 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 invention.

Claims

1. A powder-adding device for sample testing, characterized in that, The workbench includes a first powder feeding seat and a second powder feeding seat that are capable of horizontal reciprocating along a first direction. Test tube racks are respectively installed on the first powder feeding seat and the second powder feeding seat. At least one of the first powder feeding seat and the second powder feeding seat is capable of rotating along a vertical axis. A feeding assembly is installed above the workbench, positioned above the movement trajectories of the first and second powder feeding seats. The feeding assembly includes multiple material cylinders, each with a discharge port at its lower end. Each material cylinder is equipped with a feeding mechanism, and a driving mechanism is located above the material cylinder. The driving mechanism has multiple downward-facing and rotatable driving heads. At least one of the feeding assembly and the driving mechanism is capable of lifting and lowering, allowing the driving head to be vertically and detachably connected to the driving part at the top of the feeding mechanism. The driving head can rotate to drive the feeding mechanism, thereby quantitatively outputting the material from the material cylinder.

2. The powder-adding device for sample testing according to claim 1, characterized in that, The first powder filling station and / or the second powder filling station include a turntable, a support and a weighing module arranged sequentially from top to bottom. The weighing module is connected to a linear drive assembly on the workbench. The support is fixed to the weighing module. The turntable is rotatably connected to the support. The test tube rack is fixed above the turntable. The test tube rack is provided with multiple test tube ports.

3. The powder-adding device for sample testing according to claim 1, characterized in that, The material cylinder includes a detachably connected cylinder body and a top cover. The feeding mechanism includes a rotating shaft rotatably mounted on the top cover. The lower end of the rotating shaft extends to the discharge port of the cylinder body, and the lower end of the rotating shaft has a spiral conveying section.

4. The powder-adding device for sample testing according to claim 3, characterized in that, The drive unit is an insertion port located at the top of the rotating shaft. The drive mechanism includes multiple motors, and the drive head is mounted on the output shaft of the motor. The drive head coincides with the rotation axis of the rotating shaft.

5. The powder-adding device for sample testing according to any one of claims 1-4, characterized in that, A top plate is fixed above the workbench by multiple guide rods. A drive mechanism is fixed above the top plate by support rods. A lifting plate is installed below the top plate. Multiple material cylinders are installed on the lifting plate. The top plate is provided with multiple through holes for the upper ends of the material cylinders to pass through or detach.

6. The powder-adding device for sample testing according to claim 5, characterized in that, The material cylinder is rotatably connected to the lifting plate, and the lifting plate is provided with a first locking mechanism to lock the material cylinder; the material cylinder is provided with a second locking mechanism to lock the feeding mechanism; the lower end of the material cylinder forms a discharge section with a non-circular cross-section; the discharge section is provided with the discharge port; test tubes are installed on the test tube rack; the upper end of the test tube is threadedly connected to an end cap; the end cap is provided with a drive port that can be inserted into the discharge section; a sealing block is installed below the drive port to accommodate the lower end of the discharge section.

7. The powder-adding device for sample testing according to claim 6, characterized in that, The test tube rack and the test tubes are provided with a guide that is inserted vertically to restrict the rotation of the test tubes relative to the test tube inlet.

8. The powder-adding device for sample testing according to claim 6, characterized in that, The first locking element is a limiting frame located at the lower end of the driving mechanism. The limiting frame can be raised and lowered relative to the driving mechanism. The limiting frame has multiple limiting rods, and the top of the material cylinder is provided with a limiting hole for inserting into the limiting rods.

9. The powder-adding device for sample testing according to claim 6, characterized in that, The second locking component includes a locking plate rotatably mounted on the groove of the top wall of the barrel. A torsion spring and an electromagnetic attraction assembly are provided between the locking plate and the barrel. The torsion spring is used to drive the locking plate to extend out of the groove, and the magnetic attraction assembly is used to drive the locking plate to retract to the notch. A fixing plate extending radially is fixed on the driving part, and a limiting opening for accommodating the locking plate is provided on the lower surface of the fixing plate.

10. A sample pretreatment device for testing, characterized in that, It includes a frame on which a powder-adding device for sample testing as described in any one of claims 1 to 9 is mounted.

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