A friction driven precision pipette and use method thereof

Abstract

The invention discloses a friction-driven precision pipette and a method for using the same, comprising: a fixed frame and a pipette, and a driving mechanism arranged in the fixed frame; the driving mechanism comprises: a disc motor, the disc motor is fixedly connected to an outer wall of one side of the fixed frame, an inner wall of one side of the fixed frame is rotatably connected to a driving shaft, one end of an output shaft of the disc motor passes through the fixed frame and is fixedly connected to the driving shaft, a driving friction wheel is movably connected to the circumferential outer wall of the output shaft of the disc motor, and a locking nut is threadedly connected to the circumferential outer wall of the output shaft of the disc motor; a friction wheel frame is slidably connected between the inner walls of both sides of the fixed frame, and a driven friction wheel is rotatably connected between the inner walls of both sides of the friction wheel frame; by arranging a controller, a pressure sensor, a displacement sensor, an actuator and a liquid level sensor, it is ensured that key parameters in the pipetting process are controlled; by adaptively adjusting the compression degree of the compression spring and changing the radial preload, the stability of the pipette under long-term operation is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of pipettes, and in particular to a friction driven precision pipette and a use method thereof. Background Art

[0002] A pipette, also known as a pipette gun, is a precision liquid metering tool that is widely used in biology, chemistry, clinical diagnosis, environmental science, food science and other fields. Its basic structure includes a display window, a capacity adjustment component, a piston, an O-ring, a suction tube and a pipette tip. Through the telescopic movement of the piston, the precise transfer of liquid is achieved under the action of air pressure difference or positive displacement. Pipettes can be classified according to their working principle, number of channels, whether the scale is adjustable, the adjustment method and special uses.

[0003] First, after a traditional pipette has been running for a long time, due to wear or other reasons, the preload force of the friction drive system may decrease. Insufficient preload force will cause the relative displacement between the driven friction wheel and the friction shaft to change, which will further affect the liquid volume inside the pipette, resulting in fluctuations in the liquid level. The instability of the liquid level will directly affect the accuracy of the pipette, causing the performance of the pipette to significantly decrease over time and use.

[0004] Secondly, existing pipettes lack flexibility and adaptability in preload control. Once the preload is insufficient, it needs to be adjusted manually, which is not only cumbersome to operate, but also difficult to compensate for the attenuation of the preload in a timely and accurate manner. Although excessive preload can reduce slippage, it may increase mechanical wear and reduce the life and response speed of the system, which is also a problem that needs to be solved urgently.

[0005] Therefore, it is necessary to provide a friction-driven precision pipette and a method of use to solve the above-mentioned technical problems. Summary of the invention

[0006] The invention overcomes the deficiencies of the prior art and provides a friction driven precision pipette and a use method thereof.

[0007] To achieve the above-mentioned object, the technical solution adopted by the present invention is: a friction-driven precision pipette and a method of use, comprising: a fixed frame and a pipette, and a driving mechanism arranged in the fixed frame;

[0008] The driving mechanism comprises: a disc motor, the disc motor is fixedly connected to an outer wall of one side of a fixed frame, an inner wall of one side of the fixed frame is rotatably connected to a driving shaft, one end of the disc motor output shaft passes through the fixed frame and is fixedly connected to the driving shaft, a driving friction wheel is movably connected to the circumferential outer wall of the disc motor output shaft, and a locking nut is threadedly connected to the circumferential outer wall of the disc motor output shaft;

[0009] A friction wheel frame is slidably connected between the inner walls on both sides of the fixed frame, a driven friction wheel is rotatably connected between the inner walls on both sides of the friction wheel frame, a pressure cover is fixedly connected to one side of the fixed frame, a compression spring is provided between the pressure cover and the friction wheel frame, a friction shaft is transmission-connected between the driving friction wheel and the driven friction wheel, and two ends of the friction shaft respectively penetrate the top inner wall and the bottom inner wall of the fixed frame.

[0010] In a preferred embodiment of the present invention, a pipette is fixedly connected to the bottom of the fixed frame, a sealed cavity is provided in the pipette, a ceramic shaft is slidably connected in the sealed cavity, and the bottom of the friction shaft is fixedly connected to the top of the ceramic shaft.

[0011] In a preferred embodiment of the present invention, a gun tip fixing seat is provided at the bottom of the pipette, and an air replacement hole is provided at the bottom of the gun tip fixing seat.

[0012] In a preferred embodiment of the present invention, axial adjustment plates are provided between the outer walls on both sides of the driven friction wheel and the inner walls on both sides of the friction wheel frame, and photoetched lines are provided on the circumferential outer wall of the friction shaft.

[0013] In a preferred embodiment of the present invention, a pressure sensor is provided between the compression spring and the pressure cover, a displacement sensor is provided at the top end of the friction shaft, an actuator is provided between the friction wheel frame and the pressure cover, and a controller is provided on one side of the fixed frame.

[0014] In a preferred embodiment of the present invention, one side of the fixing frame is threadedly connected with two screws.

[0015] In a preferred embodiment of the present invention, a liquid level sensor is provided in the gun head fixing seat, the liquid level sensor is located at one end of the air replacement hole, and the liquid level sensor is electrically connected to the controller.

[0016] In a preferred embodiment of the present invention, the controller, pressure sensor, displacement sensor and actuator are electrically connected.

[0017] In a preferred embodiment of the present invention, a method for using a friction-driven precision pipette is as follows:

[0018] S1: Real-time monitoring and collection of the relative displacement, preload force and liquid level parameters between the driven friction wheel and the friction shaft;

[0019] S2: Receive and process the real-time monitoring data of S1, compare and analyze it with the historical data, evaluate the current displacement change rate and trend, and whether it exceeds the normal working range;

[0020] S3: Based on the analysis results, the controller determines whether the preload force needs to be adjusted to maintain system stability;

[0021] S4: The compression degree of the compression spring is adjusted by the actuator to change the radial preload force and achieve adaptive adjustment.

[0022] In a preferred embodiment of the present invention, in S4, the compression spring is a disc spring for providing an initial radial preload.

[0023] The present invention solves the defects existing in the background technology and has the following beneficial effects:

[0024] The present invention provides a friction-driven precision pipette and a method for using the same. By configuring a controller, a pressure sensor, a displacement sensor, an actuator and a liquid level sensor, key parameters in a pipetting process are ensured to be controlled. The compression degree of a compression spring is adjusted by adaptive regulation to change the radial preload force, thereby achieving stability and durability of the pipette during long-term operation.

[0025] The present invention provides a friction-driven precision pipette and a method for using the same. By setting a displacement sensor, a pressure sensor and a liquid level sensor, the relative displacement between a driven friction wheel and a friction shaft, the radial preload force and the liquid level in the pipette can be monitored in real time, and subtle changes in the pipetting process can be fed back in real time. The direct effect is to improve the accuracy of the pipetting operation, thereby solving the problem of relative displacement fluctuation caused by insufficient preload force, which in turn affects the pipetting accuracy.

[0026] The present invention provides a friction-driven precision pipette and a method for using the same. The actuator adjusts the degree of compression of the disc spring in real time according to sensor data, thereby changing the radial preload force. The adaptive adjustment in step S4 can effectively compensate for the attenuation of the preload force caused by long-term use, extend the service life of the pipette, and reduce sliding or wear caused by insufficient preload force. The device significantly improves the stability and durability of the pipette, and further reduces maintenance costs and downtime.

[0027] The present invention provides a friction-driven precision pipette and a method for using the same. Through the detection and collection in step S1 and the adaptive adjustment in step S4, not only the high precision and stability of the pipetting operation are achieved, but also the durability and maintenance efficiency of the pipette are significantly improved, so that the pipette can maintain stability under various experimental conditions and meet the high requirements for pipetting accuracy and efficiency in work. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 is a top view of the internal structure of the device body of a preferred embodiment of the present invention;

[0030] Figure 2 It is a front view structural diagram of the device body of a preferred embodiment of the present invention;

[0031] Figure 3 is a three-dimensional structural diagram of the appearance of the device body of a preferred embodiment of the present invention;

[0032] Figure 4 is a schematic diagram of the use process of the device body of the preferred embodiment of the present invention;

[0033] Figure 5 It is a schematic diagram of a device of Embodiment 2 of the preferred embodiment of the present invention.

[0034] In the figure: 1. screw; 2. driving friction wheel; 3. locking nut; 4. disc motor; 5. driven friction wheel; 6. axial adjustment plate; 7. compression spring; 8. friction wheel frame; 9. pressure cover; 10. friction shaft; 11. driving shaft; 12. ceramic shaft; 13. sealing chamber; 14. gun head fixing seat; 15. fixing frame; 16. pipette. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0037] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the invention, unless otherwise specified, "multiple" means two or more.

[0038] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood by specific circumstances.

[0039] like Figure 1 As shown, the present invention provides a friction-driven precision pipette, comprising: a fixed frame 15 and a pipette 16, and a driving mechanism disposed in the fixed frame 15;

[0040] like Figure 1 - Figure 2 As shown, the driving mechanism includes: a disc motor 4, the disc motor 4 is fixedly connected to the outer wall of one side of the fixed frame 15, the inner wall of one side of the fixed frame 15 is rotatably connected to the driving shaft 11, one end of the output shaft of the disc motor 4 passes through the fixed frame 15 and is fixedly connected to the driving shaft 11, the circumferential outer wall of the output shaft of the disc motor 4 is movably connected to the driving friction wheel 2, and the circumferential outer wall of the output shaft of the disc motor 4 is threadedly connected to the locking nut 3;

[0041] like Figure 1 - Figure 2As shown, a friction wheel frame 8 is slidably connected between the inner walls on both sides of the fixed frame 15, a driven friction wheel 5 is rotatably connected between the inner walls on both sides of the friction wheel frame 8, a pressure cover 9 is fixedly connected to one side of the fixed frame 15, a compression spring 7 is provided between the pressure cover 9 and the friction wheel frame 8, a friction shaft 10 is transmission-connected between the driving friction wheel 2 and the driven friction wheel 5, and the two ends of the friction shaft 10 respectively penetrate the top inner wall and the bottom inner wall of the fixed frame 15. A pipette 16 is fixedly connected to the bottom of the fixed frame 15, a sealed cavity 13 is provided in the pipette 16, a ceramic shaft 12 is slidably connected in the sealed cavity 13, the bottom of the friction shaft 10 is fixedly connected to the top of the ceramic shaft 12, a gun head fixing seat 14 is provided at the bottom of the pipette 16, and an air replacement hole is provided at the bottom of the gun head fixing seat 14;

[0042] It should be noted that: the disc motor 4 serves as a power source and stably transmits power to the drive shaft 11. The driving friction wheel 2 is fixed on the output shaft of the disc motor 4, and transmits power to the friction shaft 10 through friction with the driven friction wheel 5. The friction shaft 10 connects the two friction wheels to ensure power transmission, and is equipped with photolithography lines and displacement sensors to realize liquid transfer control. The pressure sensor monitors the pressure of the driven friction wheel 5, and automatically adjusts it through the controller and actuator to keep the friction force stable. The axial adjustment plate 6 can fine-tune the position of the driven friction wheel 5. The ceramic shaft 12 cooperates with the sealing chamber 13 to ensure sealing, and the sliding connection realizes precise liquid transfer. The air replacement hole on the gun head fixing seat 14 ensures the accuracy of pipetting;

[0043] like Figure 1 - Figure 3 As shown, axial adjustment sheets 6 are provided between the outer walls on both sides of the driven friction wheel 5 and the inner walls on both sides of the friction wheel frame 8, photoetching lines are provided on the circumferential outer wall of the friction shaft 10, a pressure sensor is provided between the compression spring 7 and the pressure cover 9, a displacement sensor is provided at the top of the friction shaft 10, an actuator is provided between the friction wheel frame 8 and the pressure cover 9, a controller is provided on one side of the fixing frame 15, two screws 1 are threadedly connected to one side of the fixing frame 15, a liquid level sensor is provided in the gun head fixing seat 14, the liquid level sensor is located at one end of the air replacement hole, the liquid level sensor is electrically connected to the controller, and the controller, the pressure sensor, the displacement sensor and the actuator are electrically connected;

[0044] It should be noted that the liquid level sensor is located at one end of the air displacement hole and can monitor the height of the liquid in real time to ensure the accuracy of the pipetting. The controller receives signals from the pressure sensor, displacement sensor, actuator and liquid level sensor, collects and adjusts them, and realizes pipetting control. The fixing frame 15 is fixed in an appropriate position by screws 1.

[0045] like Figure 3 As shown, a method for using a friction-driven precision pipette comprises the following steps:

[0046] S1: real-time monitoring and collection of parameters of the relative displacement, preload force and liquid level height between the driven friction wheel 5 and the friction shaft 10;

[0047] S2: Receive and process the real-time monitoring data of S1, compare and analyze it with the historical data, evaluate the current displacement change rate and trend, and whether it exceeds the normal working range;

[0048] S3: Based on the analysis results, the controller determines whether the preload force needs to be adjusted to maintain system stability;

[0049] S4: The compression degree of the compression spring 7 is adjusted by the actuator to change the radial preload force and realize adaptive adjustment.

[0050] It should be noted that: in S1, the sensor continuously monitors and collects the relative displacement between the driven friction wheel 5 and the friction shaft 10, the size of the preload force, and the height parameters of the liquid level to provide basic data for the precise control of the system. The data collected in S1 is received in S2, and compared and analyzed with historical data to evaluate the current state of the system. Based on these analysis results, the controller in S3 will intelligently determine whether the preload force needs to be adjusted to ensure the stability of the system and the accuracy of pipetting. Once it is determined that adjustment is required, S4 will start, and the compression degree of the compression spring 7 will be accurately adjusted through the actuator, thereby changing the radial preload force and realizing adaptive adjustment of the system, thereby ensuring the high precision and stability of the friction-driven precision pipette during the pipetting process. Embodiment 1

[0051] like Figure 3 As shown, a method for using a friction-driven precision pipette comprises the following steps:

[0052] S1: real-time monitoring and collection of parameters of the relative displacement, preload force and liquid level height between the driven friction wheel 5 and the friction shaft 10;

[0053] S2: Receive and process the real-time monitoring data of S1, compare and analyze it with the historical data, evaluate the current displacement change rate and trend, and whether it exceeds the normal working range;

[0054] S2.1: Calculate the current displacement change rate and trend;

[0055] Among them: The calculation formula of displacement change rate is:

[0056]

[0057] Among them: The calculation formula of displacement trend is:

[0058]

[0059] S2.2: Compare the current displacement with the preset normal working range. If the displacement exceeds the set threshold, proceed to the next step; otherwise, continue real-time monitoring;

[0060] if or , go to the next step; otherwise continue real-time monitoring;

[0061] S2.3: Combined with other sensor data (such as pressure sensor, liquid level sensor), comprehensively judge whether there is indeed a problem of insufficient preload force;

[0062] if or (in is the actual liquid level, Target liquid level height), it is considered that the preload force is insufficient and proceed to the next step;

[0063] S3: Based on the analysis results, the controller determines whether the preload force needs to be adjusted to maintain system stability;

[0064] S3.1: If it is determined that the preload force is insufficient, the controller calculates the preload force increment that needs to be adjusted according to a preset control algorithm (such as PID control);

[0065] The preload increment is calculated using the PID control algorithm:

[0066]

[0067] in:

[0068] is the error signal; , , are the proportional, integral and differential coefficients of the PID controller; is the target preload;

[0069] S3.2: Sending an adjustment command to the actuator to increase the compression degree of the compression spring 7 to increase the pre-tightening force;

[0070] New preload after adjustment: ;

[0071] S3.3: Immediately re-monitor the displacement, preload and liquid level after adjustment to confirm the effect of the adjustment;

[0072] Check whether the liquid level has returned to the target value: ;

[0073] If the liquid level returns to normal, continue real-time monitoring; otherwise, further adjust the preload;

[0074] S4: The actuator adjusts the compression degree of the disc spring, changes the radial preload, and realizes adaptive adjustment;

[0075] S4.1: After each adjustment, the controller continues to monitor the performance of the system, including pipetting accuracy, response speed, and liquid level stability;

[0076] Calculate pipetting accuracy: ;

[0077] Calculate the response time: ;

[0078] Monitoring of liquid level stability: ;

[0079] S4.2: If the system performance does not return to normal, further fine-tune the preload until the ideal state is achieved;

[0080] if or , further adjust the preload:

[0081]

[0082] in: ;

[0083] S4.3: Record the results of each adjustment and form a historical database for subsequent analysis and optimization;

[0084] Historical data: .

[0085] In general: real-time monitoring and collection of the relative displacement, preload and liquid level parameters between the driven friction wheel 5 and the friction shaft 10, to provide real-time data support for the controller. After receiving the data collected in S1, historical data comparison and current state analysis are performed, the displacement change rate and trend are calculated, and the system state is determined. If the preload needs to be adjusted to maintain system stability, the controller will calculate the preload increment according to the PID control algorithm, and adjust the compression degree of the compression spring 7 through the actuator to achieve adaptive adjustment. After each adjustment, the controller continues to monitor the performance of the system, including pipetting accuracy, response speed and liquid level stability. If the system performance has not returned to normal, the preload is further fine-tuned until the ideal state is reached. At the same time, the results of each adjustment are recorded to form a historical database for subsequent analysis and optimization. Embodiment 2

[0086] like Figure 5 As shown, the second embodiment is innovative based on the first embodiment, so that the driving mechanism can be connected to a connecting plate, and a plurality of pipettes 16 can be arranged at the bottom of the connecting plate, thereby realizing the function of multi-channel pipetting and improving the pipetting efficiency.

[0087] When the multi-channel pipetting function is used, the output shaft of the disc motor 4 drives the driving friction wheel 2 to rotate. The driving friction wheel 2 and the driven friction wheel 5 transmit power through friction, so that the driven friction wheel 5 drives the friction shaft 10 to move up and down. Since the bottom of the friction shaft 10 is fixedly connected to the connecting plate, the connecting plate will also move up and down accordingly. Several pipettes 16 at the bottom of the connecting plate will move synchronously therewith to realize the function of multi-channel pipetting. During the pipetting process, the accuracy and stability of the pipetting can be ensured through real-time monitoring of the controller, pressure sensor, displacement sensor and liquid level sensor. At the same time, the compression degree of the compression spring 7 can be adjusted according to the real-time monitoring data through the adaptive adjustment mechanism, thereby changing the radial preload force to ensure the stability and durability of the pipette under long-term operation.

[0088] The above is based on the ideal embodiment of the present invention. Through the above description, relevant personnel can make various changes and modifications without departing from the technical concept of the present invention. The technical scope of the present invention is not limited to the content in the specification, and the technical scope must be determined according to the scope of the claims.

Claims

1. A friction-driven precision pipette, comprising: A fixed frame (15) and a pipette (16), and a driving mechanism arranged in the fixed frame (15), characterized in that: The driving mechanism comprises: a disc motor (4), the disc motor (4) being fixedly connected to an outer wall of one side of a fixing frame (15), an inner wall of one side of the fixing frame (15) being rotatably connected to a driving shaft (11), one end of an output shaft of the disc motor (4) passing through the fixing frame (15) and being fixedly connected to the driving shaft (11), a driving friction wheel (2) being movably connected to the circumferential outer wall of the output shaft of the disc motor (4), and a locking nut (3) being threadedly connected to the circumferential outer wall of the output shaft of the disc motor (4); A friction wheel frame (8) is slidably connected between the inner walls on both sides of the fixed frame (15), a driven friction wheel (5) is rotatably connected between the inner walls on both sides of the friction wheel frame (8), a pressure cover (9) is fixedly connected to one side of the fixed frame (15), a compression spring (7) is provided between the pressure cover (9) and the friction wheel frame (8), a friction shaft (10) is transmission-connected between the driving friction wheel (2) and the driven friction wheel (5), and two ends of the friction shaft (10) respectively penetrate the top inner wall and the bottom inner wall of the fixed frame (15); A pipette (16) is fixedly connected to the bottom of the fixed frame (15), a gun head fixing seat (14) is provided at the bottom of the pipette (16), an air replacement hole is provided at the bottom of the gun head fixing seat (14), a pressure sensor is provided between the compression spring (7) and the pressure cover (9), a displacement sensor is provided at the top of the friction shaft (10), an actuator is provided between the friction wheel frame (8) and the pressure cover (9), a controller is provided on one side of the fixed frame (15), a liquid level sensor is provided in the gun head fixing seat (14), and the liquid level sensor is located at one end of the air replacement hole, and the controller, the liquid level sensor, the pressure sensor, the displacement sensor and the actuator are electrically connected; According to the data monitored by the displacement sensor, the liquid level sensor and the pressure sensor, the compression degree of the compression spring (7) is adjusted in real time through the actuator.

2. A friction-driven precision pipette according to claim 1, characterized in that: A sealed cavity (13) is provided in the pipette (16), a ceramic shaft (12) is slidably connected in the sealed cavity (13), and the bottom of the friction shaft (10) is fixedly connected to the top of the ceramic shaft (12).

3. A friction driven precision pipette according to claim 1, characterized in that: Axial adjustment plates (6) are provided between the outer walls on both sides of the driven friction wheel (5) and the inner walls on both sides of the friction wheel frame (8), and the circumferential outer wall of the friction shaft (10) is provided with photoetched lines.

4. A friction driven precision pipette according to claim 1, characterized in that: Two screws (1) are threadedly connected to one side of the fixing frame (15).

5. A method for using a friction-driven precision pipette according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1: real-time monitoring and collection of parameters of the relative displacement, preload force and liquid level height between the driven friction wheel (5) and the friction shaft (10); S2: Receive and process the real-time monitoring data of S1, compare and analyze it with the historical data, evaluate the current displacement change rate and trend, and whether it exceeds the normal working range; S3: Based on the analysis results, the controller determines whether the preload force needs to be adjusted to maintain system stability; S4: The compression degree of the compression spring (7) is adjusted by the actuator to change the radial preload force and realize adaptive adjustment.

6. The method for using a friction-driven precision pipette according to claim 5, characterized in that: In S4, the compression spring (7) is a disc spring, which is used to provide an initial radial preload.

Images