Automatic calibration device and method for pipettor

Abstract

The invention discloses an automatic calibration device and method for a pipettor. The device comprises a pipettor bracket, a suction head box, a liquid storage device and a weighing device, the acquisition mechanism is used for acquiring model information of the pipettor; the cooperative arm is used for controlling the pipettor to move; the gear shifting mechanism is used for adjusting the volume display of the pipettor according to the measuring point; the electric cylinder is used for controlling the pipettor to suck or discharge liquid; the wiping mechanism is used for sucking and removing wall-mounted liquid drops from the suction head; the visual detection mechanism is used for confirming the volume display of the pipettor and judging whether liquid remains on a suction head of the pipettor or not; and the upper computer is used for controlling the operation of the cooperative arm, the gear shifting mechanism, the electric cylinder and the suction head clamp according to the information sent by the acquisition mechanism and the visual inspection mechanism. According to the invention, automatic calibration of pipettors of various brands and various capacities can be realized, errors are reduced by combining a visual detection technology, and the calibration efficiency and accuracy are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of pipette calibration, and in particular to an automatic pipette calibration device and method. Background Art

[0002] Currently, pipette calibration still relies on manual labor, a traditional method that is cumbersome, labor-intensive, and inefficient. Because pipettes come in a variety of styles, each with its own unique measurement point capacities, operators must frequently consult the corresponding manual before taking measurements, significantly reducing calibration efficiency.

[0003] In addition, during the manual calibration process, key operating steps such as gear adjustment, liquid aspiration, and liquid discharge must be completed by the operator with the naked eye. This method is not only prone to operational errors due to human factors, but may also cause problems such as excessive aspiration and insufficient liquid discharge due to improper operation, which in turn causes deviations in experimental data, affecting the accurate judgment of whether the pipette is qualified, and further reducing the overall efficiency and quality of the calibration work. Summary of the Invention

[0004] The purpose of the present invention is to solve the problems in the prior art.

[0005] The technical solution adopted by the present invention to solve the technical problem is to provide an automatic calibration device for a pipette, comprising:

[0006] Pipette holder, used to place pipettes;

[0007] A collecting mechanism, used for collecting model information of the pipette;

[0008] a collaborative arm for controlling pipette movement;

[0009] Tip box, used to place tips;

[0010] A shifting mechanism for adjusting the volume display of the pipette according to the measuring point;

[0011] A liquid reservoir, used to contain liquid for calibration;

[0012] Electric cylinder, used to control the pipette to aspirate or dispense liquid;

[0013] Wiping mechanism, used to remove droplets hanging on the wall of the suction head;

[0014] A visual inspection mechanism for confirming the volume display of the pipette and determining whether there is liquid residue in the pipette tip;

[0015] Tip holder, used to remove the tip from the pipette;

[0016] A weighing device, used to detect the volume of the liquid discharged by the pipette;

[0017] The host computer is used to control the operation of the collaborative arm, gear adjustment mechanism, electric cylinder and suction head clamp according to the information sent by the acquisition mechanism and visual detection mechanism.

[0018] Preferably, the acquisition mechanism includes a first camera and a sticker printed with a QR code; the sticker is affixed to the pipette body, and the QR code on the sticker includes the model information of the pipette; the first camera is used to acquire the QR code information and send it to the host computer.

[0019] Preferably, the gear shifting mechanism includes a driving gear, two driven gears, two rubber wheels, and a drive motor; the gear shifting mechanism fixes the pulley through the two rubber wheels; the drive motor controls the rotation of the driving gear, the driving gear drives the two driven gears to rotate, and the two driven gears respectively drive the two rubber wheels to rotate, thereby driving the pulley to rotate and changing the capacity display of the pipette.

[0020] Preferably, the wiping mechanism includes a drum, a fixed drum, a drive motor and filter paper; the fixed drum is rigidly fixed to the work surface by a first bracket, and the drive motor is rigidly fixed to the work surface by a second bracket; the rolled filter paper is mounted on the fixed drum, and the free end of the filter paper is drawn out from the fixed drum and wrapped around the outer circumference of the drum, so that the filter paper between the drum and the fixed drum is in a tensioned and straightened state; the drive motor is used to drive the rotating drum to rotate, and the filter paper segment that has been wiped is rolled into the drum for storage, and at the same time, the tightening force of the filter paper is used to drive the filter paper roll on the fixed drum to rotate, so that a new unused filter paper segment is drawn out from the front end of the fixed drum.

[0021] Preferably, the visual detection mechanism includes a second camera and a visual detection module, the second camera is used to capture images, and the visual detection module is used to make judgments based on the images captured by the second camera; including the following situations:

[0022] The second camera captures an image of the pipette's capacity display, and the visual detection module determines the current value of the capacity display;

[0023] The second camera captures an image of the pipette tip, and the visual inspection module determines whether there is liquid attached to the outside of the tip;

[0024] The second camera captures the image of the pipette tip, and the visual inspection module determines whether there is any liquid residue inside the tip.

[0025] The present invention also provides a method for automatic calibration of a pipette, using any of the above-mentioned automatic calibration devices for a pipette, comprising the following steps:

[0026] In the input step, the user enters the model information of the pipette to be calibrated into the host computer, and affixes the QR code sticker containing the model information to the pipette gun body, and finally places the pipette on the pipette holder;

[0027] In the identification step, the collection mechanism collects the model information of the pipette and uploads it to the host computer; the host computer confirms the pipette model, sets the measurement point according to the pipette model, and controls the collaborative arm to clamp the pipette;

[0028] Preparation step: Move the pipette to the tip box and put on the appropriate tip, then move it to the adjustment mechanism and adjust the pipette volume display to the measurement point;

[0029] In the liquid aspiration step, the pipette is moved to the liquid reservoir and the pipette is controlled by the electric cylinder to aspirate the liquid;

[0030] In the wiping step, filter paper is used to remove the liquid on the pipette tip. Then, the visual detection mechanism is used to collect the liquid residual information of the pipette tip to determine whether there is still liquid on the outside of the pipette tip. If so, the wiping step is performed again. Otherwise, the liquid discharge step is entered.

[0031] In the liquid discharge step, the pipette is moved to the weighing device, and the electric cylinder presses the knob of the pipette to control the pipette to discharge liquid; the visual detection mechanism is used to collect liquid residual information to determine whether there is liquid residual in the tip. If so, the liquid is discharged again, otherwise the first repetition step is entered;

[0032] The first repeating step is to keep the measuring point unchanged, repeat the preparation step to the discharge step several times, record the difference between the weighing data of each weighing machine and the weighing data of multiple weighing machines, and complete the calibration of the measuring point;

[0033] The second repetition step changes the measuring point and repeats the preparation step to the first repetition step several times to complete the calibration of multiple measuring points;

[0034] The judgment step is to judge whether the pipette is qualified according to the calibration results of each measurement point.

[0035] Preferably, the shifting mechanism adjusts the volume display of the pipette to the measuring point, comprising the following steps:

[0036] The cooperative arm moves the pipette to the gear-shifting mechanism so that its pulley is fixed between the two rubber wheels of the gear-shifting mechanism, and then releases the pipette;

[0037] The drive motor of the gear adjustment mechanism controls the rotation of the driving gear, which drives the pulley to rotate, thereby changing the volume display of the pipette;

[0038] The visual inspection mechanism records the pipette's capacity display in real time and uploads it to the host computer. When the capacity reaches the required measurement point, the host computer controls the gear adjustment mechanism to stop rotating;

[0039] The cooperative arm re-grips the pipette and moves the pulley of the pipette out from between the two rubber wheels of the gear adjustment mechanism.

[0040] Preferably, the wiping step comprises the following steps:

[0041] Move the pipette to the wiping mechanism and hold the pipette vertically;

[0042] Use the multiple-touch method to wipe. Each time you touch, move the pipette to the side of the filter paper, positioning the tip of the pipette 2 to 3 mm below the surface of the stretched filter paper. Then, move the pipette horizontally at a constant speed until the outer edge of the tip touches the edge of the filter paper, ensuring that the tip of the pipette is always in non-contact with the filter paper.

[0043] Move the pipette to the visual inspection mechanism to check whether there is liquid hanging on the outside of the tip; if liquid is detected on the outside of the tip, move the pipette to the wiping mechanism and wipe again until no residual liquid is detected on the wall, and then end the wiping operation.

[0044] Preferably, the drainage step comprises the following steps:

[0045] Move the pipette to the weighing machine and insert the pipette tip into the weighing cup inside the weighing machine;

[0046] Adjust the pressing force of the electric cylinder, press the knob to the first stop, wait 1 to 2 seconds, and then press the button fully to the second stop;

[0047] Move the pipette to the visual inspection mechanism for droplet visual inspection to check whether there is any liquid residue in the tip;

[0048] If residual liquid is detected in the tip, the pipette is moved to the weighing cup and the liquid is discharged again until it is confirmed that there is no liquid residual in the tip, and the discharge operation is ended; if residual liquid is still detected in the tip after the Kth discharge, the tip on the pipette is removed by the tip clamp, the pipette is moved to the tip box and a new tip is put on, and then the pipette is returned to the aspiration step; K times is the preset threshold.

[0049] Preferably, if there are multiple pipettes to be calibrated, in the input step, the user numbers the pipettes, generates a QR code using the numbers and corresponding model information of all pipettes, pastes them to the corresponding pipettes respectively, and finally inputs the numbers and corresponding model information into the host computer; the host computer calibrates the pipettes in sequence according to the numbers, and the calibration includes an identification step to a judgment step.

[0050] The present invention has the following beneficial effects:

[0051] (1) The present invention utilizes a collection mechanism to realize model judgment, and combines a gear adjustment mechanism to select a measuring point, thereby realizing automatic calibration of pipettes of different styles and capacities, and is highly practical; and can realize automatic calibration of multiple pipettes at one time, thus achieving high-efficiency calibration of pipettes;

[0052] (2) The present invention reduces the errors caused by the liquid aspiration and discharge processes and improves the calibration accuracy by adding a wiping step and a tip droplet residue detection step.

[0053] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, but the present invention is not limited to the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 This is a schematic diagram of an automatic pipette calibration device according to an embodiment of the present invention;

[0055] Figure 2 A top view of an automatic pipette calibration device according to an embodiment of the present invention;

[0056] Figure 3 This is a schematic diagram of a collection mechanism of a pipette automatic calibration device according to an embodiment of the present invention;

[0057] Figure 4 This is a schematic diagram of the gear adjustment of an automatic calibration device for a pipette according to an embodiment of the present invention;

[0058] Figure 5 This is a schematic diagram of a wiping mechanism of an automatic pipette calibration device according to an embodiment of the present invention;

[0059] Figure 6 A diagram showing the steps of a method for automatic pipette calibration according to an embodiment of the present invention;

[0060] Figure 7 A schematic diagram of a pipette tip in accordance with an automatic pipette calibration method according to an embodiment of the present invention;

[0061] Figure 8 A schematic diagram of the liquid aspiration operation of a pipette automatic calibration method according to an embodiment of the present invention;

[0062] Figure 9 A schematic diagram of a wiping operation of a pipette automatic calibration method according to an embodiment of the present invention;

[0063] Figure 10 A schematic diagram of the liquid discharging operation of a pipette automatic calibration method according to an embodiment of the present invention;

[0064] Figure 11 This is a schematic diagram of the tip replacement operation in a pipette automatic calibration method according to an embodiment of the present invention;

[0065] Figure markings: 0-host computer, 11-bottom end of pipette, 12-pipette gun body, 13-pipette capacity display area, 14-pipette knob, 15-tip, 2-collaborative arm, 21-clamp, 22-electric cylinder, 3-pipette holder, 4-tip box, 5-gear adjustment mechanism, 51-driving gear, 52-driven gear, 53-rubber wheel, 54-drive motor, 55-holder, 61-first camera, 62-QR code sticker, 7-liquid reservoir, 81-second camera, 9-wiping mechanism, 91-holder, 92-holder, 93-drive motor, 94-reel, 95-filter paper, 96-fixed cylinder, 10-balance, 11-material box, 12-tip clamp. DETAILED DESCRIPTION

[0066] See also Figure 1 and Figure 2 As shown, it is a schematic diagram and a top view of an automatic calibration device for a pipette according to an embodiment of the present invention, comprising a host computer 0, a collaborative arm 2, a pipette holder 3, a tip box 4, a gear adjustment mechanism 5, a collection mechanism, a liquid reservoir 7, a visual inspection mechanism, a wiping mechanism 9, a balance 10, a material box 11 and a tip gripper 12; wherein, the host computer comprises an input device (keyboard and mouse) and an output device (display), the collaborative arm 2 clamps the pipette through the clamp 21, and controls the pipette to aspirate or discharge liquid through the electric cylinder 22; the collection mechanism comprises a first camera 61 and a QR code 62, and the visual inspection mechanism comprises a second camera 81 and a visual inspection module; the entire workbench (excluding the host computer and the balance) is 1.2 meters long and 1.2 meters wide.

[0067] See also Figure 3 Figure 2 shows a schematic diagram of the data acquisition mechanism of an automatic pipette calibration device according to an embodiment of the present invention. The data acquisition mechanism includes a QR code sticker 62 and a first camera 61. The first camera 61 is mounted on the collaborative arm 2 and facilitates confirmation of the pipette model information before gripping. The QR code sticker 62 is affixed to the pipette body. The pipette includes a pipette base 11 for connecting to a tip 15, a pipette body 12, a volume display area 13, and a knob 14.

[0068] See also Figure 4The figure shows a schematic diagram of the shift mechanism of a pipette automatic calibration device according to an embodiment of the present invention. The shift mechanism comprises a driving gear 51, a driven gear 52, a rubber wheel 53, a drive motor 54, and a bracket 55. The shift mechanism is fixed to a workbench via the bracket 55. The drive motor 54 is rigidly fixed to the top of the bracket 55, and its output shaft is coaxially mounted on the driving gear 51. The driving gear 51 is connected to the driven gears 52 on both sides via a precision meshing transmission pair. The two driven gears 52 are coaxially mounted on the transmission shaft in the middle of the bracket 55 with the two rubber wheels 53, respectively, to ensure that when the driven wheels 52 rotate, they drive the lower rubber wheels 53 to rotate synchronously in the same direction. After the nozzle is installed, the shift operation is performed. The clamp 21 grasps the pipette and positions its pulley to the symmetrical center position of the two sets of rubber wheels 53, forming a friction transmission contact pair. The drive motor 54 in the shift mechanism 5 controls the middle driving gear 51 to drive the rubber wheels 53 to rotate. The rubber wheels 53 rotate due to friction with the pipette pulley, thereby changing the pipette's volume display. The driving motor 54 of the gear shifting mechanism 5 is linked to the visual detection mechanism, and the second camera 81 is vertically integrated on the inner side of the bracket 55, with its lens optical axis facing the capacity display area 13 of the pipette; in the process of the gear shifting mechanism 5 rotating the pulley, the second camera 81 of the visual detection mechanism collects the image of the capacity display area 13 on the pipette in real time and uses the visual detection module to identify the current capacity. When the capacity reaches the required measuring point, the gear shifting mechanism 5 stops rotating and the gear shifting function is completed.

[0069] See also Figure 5The figure shows a schematic diagram of the wiping mechanism of a pipette automatic calibration device according to an embodiment of the present invention, which comprises a bracket 91, a bracket 92, a drive motor 93, a reel 94, filter paper 95, and a fixed barrel 96. The fixed barrel 96 is rigidly fixed to the work surface by the bracket 91, and the drive motor 93 is rigidly fixed to the work surface by the bracket 92. The drive motor 93 can drive the reel 94 to rotate. The roll of filter paper 94 is mounted on the fixed barrel 96. When in use, the free end of the filter paper 94 is drawn out from the fixed barrel 96 and wrapped around the outer periphery of the reel 94, so that the filter paper 94 between the reel 94 and the fixed barrel 96 is in a tensioned and straightened state. When wiping is completed, the drive motor 93 rotates the reel in the forward direction, rolling the wiped filter paper segment into the reel 94 for storage. At the same time, the filter paper roll on the fixed barrel 96 is driven by the tightening force of the filter paper paper to rotate, so that a new, unused filter paper segment is drawn out from the front end of the fixed barrel 96, forming a continuous replacement mechanism for the filter paper 95. A hollow roll of filter paper is mounted on a fixed cylinder. During use, the free end of the filter paper is pulled out of the cylinder and wrapped around the outer circumference of the roll, keeping the filter paper tensioned and straightened between the roll and the fixed cylinder. The filter paper is suspended from a wiping mechanism on the side of the pipette. To wipe the pipette, the gripper grasps the pipette and slowly moves it vertically downward to the filter paper. Using a multi-point touch method, the pipette tip is first positioned 2 to 3 mm below the surface of the tensioned filter paper. The pipette is then moved horizontally at a constant speed, allowing the outer edge of the tip to lightly touch the edge of the filter paper. This removes any residual liquid adhering to the outer wall of the tip while ensuring that the tip remains in contact with the filter paper to prevent capillary absorption of liquid within the tip. After one touch, the pipette is rotated horizontally 120° for the next touch, and three touches are performed to ensure that any excess liquid on the outer surface of the tip is completely absorbed by the filter paper. After wiping is complete, the pipette is moved to the position of the second camera 81 for visual inspection of droplets to check for any liquid adhering to the outer surface of the tip. If liquid is detected on the outside of the tip, move the pipette to the wiping mechanism and wipe the tip again until the test confirms that there is no residual liquid on the wall before proceeding to the next step.

[0070] See also Figure 6 FIG. 1 is a diagram showing the steps of a method for automatic pipette calibration according to an embodiment of the present invention, comprising the following steps:

[0071] S601, input step, the user enters the model information of the pipette to be calibrated into the host computer, and sticks the QR code sticker containing the model information to the pipette gun body, and finally places the pipette on the pipette holder;

[0072] S602, identification step, the collection mechanism collects the model information of the pipette and uploads it to the host computer; the host computer confirms the pipette model, sets the measurement point according to the pipette model, and controls the collaborative arm to clamp the pipette;

[0073] S603, a preparation step, moving the pipette to the tip box and putting on an appropriate tip, then moving the pipette to the adjustment mechanism and adjusting the volume display of the pipette to the measurement point;

[0074] S604, aspiration step, moving the pipette to the beaker and controlling the pipette to aspirate;

[0075] S605, wiping step, using filter paper to remove the liquid on the outside of the pipette tip, then using the visual detection mechanism to collect information about the liquid residue on the outside of the pipette tip to determine whether there is still liquid on the outside of the pipette tip. If yes, then the wiping step is repeated, otherwise the process proceeds to the draining step;

[0076] S606, a liquid discharge step, wherein the pipette is moved to the weighing cup on the balance, and the electric cylinder presses the knob of the pipette to control the pipette to discharge liquid; a visual detection mechanism is used to collect information about the residual liquid in the pipette tip to determine whether there is residual liquid in the pipette tip. If so, the liquid is discharged again; otherwise, the process proceeds to the first repetition step;

[0077] S607, first repetition step, keeping the measuring point unchanged, repeating the preparation step to the liquid discharge step several times, recording the difference between each balance measurement data and the multiple balance measurement data, and completing the calibration of the measuring point;

[0078] S608, second repetition step, changing the measurement point, repeating the preparation step to the first repetition step several times to complete the calibration of multiple measurement points;

[0079] S609, a judgment step, judging whether the pipette is qualified according to the calibration result of each measurement point.

[0080] Specifically, in S601, the user must first perform a visual inspection on the pipette to ensure that the plastic housing is flat and smooth, free of visible shrinkage, scrapped edges, cracks, bubbles, or deformation. The metal surface coating must be free of peeling, rust, or delamination. Pipette(s) that meet these requirements after manual inspection will have a QR code sticker 62 affixed to their surface.

[0081] Specifically, in S602, the acquisition mechanism uses the first camera 61 to scan the QR code sticker 62 on the surface of the pipette. This step is intended to confirm the pipette model information, ensure the accuracy of subsequent operations, and prevent the pipette from being pinched. The first camera 61 scans the code and uploads it to the host computer, which decodes and verifies the information in the QR code. Only after confirming that the model meets the requirements will the next step be taken.

[0082] Specifically, in S603, the pipette is moved to the tip box 4 and fitted with a suitable tip. Figure 7As shown, the connection between the pipette base 11 and the tip 15 is tapered to facilitate a tight connection between the two. After the clamp 21 grasps the pipette, it is precisely moved to the position directly above the determined tip 15, and then the pipette is moved vertically downward, pressing the tip 15 to connect tightly with the pipette base 11 to ensure a secure installation. After installation is complete, proceed to the next step.

[0083] Specifically, in S603, adjusting the volume display of the pipette to the measurement point using the shift mechanism includes the following steps:

[0084] S6301, the collaborative arm moves the pipette to the gear adjustment mechanism so that its pulley is fixed between the two rubber wheels of the gear adjustment mechanism, and then releases the pipette;

[0085] S6302, the drive motor of the gear adjustment mechanism controls the rotation of the driving gear, which drives the pulley to rotate, thereby changing the volume display of the pipette;

[0086] S6303: The visual inspection mechanism records the pipette's capacity display in real time and uploads it to the host computer. When the capacity reaches the required measurement point, the host computer controls the gear adjustment mechanism to stop rotating.

[0087] S6304: The collaborative arm re-grips the pipette and moves the pipette's pulley out from between the two rubber wheels of the shifting mechanism, preparing for the next step.

[0088] Specifically, the liquid aspiration operation in S604 is described in Figure 8 As shown, during the pipetting operation, the clamping jaws 21 clamp the pipette and move it above the reservoir 7 (a beaker or other container can be used) filled with distilled water, keeping the pipette vertically clamped, and using the electric cylinder 22 to slowly and accurately press the knob 14 to the first stop point. Subsequently, the pipette tip is immersed in the distilled water in the beaker, ensuring that the pipette tip is 2mm to 3mm below the liquid surface. Slowly release the knob 14, wait for 1 to 2 seconds, and then lift the pipette tip from the liquid surface. Taking the measuring point of 20μL as an example, when a slow and uniform pressure of 5N is applied to the pipette adjustment knob 14, the knob 14 will move linearly to the first stop point; because the applied force value does not reach the threshold, the knob 14 cannot overcome the resistance of the internal mechanical structure and continue to move downward. Only when the pressing load increases to 20N can the knob 14 break through the resistance threshold and complete the full stroke movement under continuous pressure drive, reaching the second stop point of the mechanical limit, which is the bottom.

[0089] Specifically, the wiping operation in S605 is shown in FIG. Figure 9 As shown, the following steps are included:

[0090] S6601, move the pipette to the wiping mechanism and keep the pipette clamped vertically;

[0091] For S6602, use the multiple-touch method. For each touch, move the pipette to the side of the filter paper, positioning the tip 2–3 mm below the surface of the stretched filter paper. Then, move the pipette horizontally at a constant speed until the outer edge of the tip touches the edge of the filter paper, ensuring that the tip remains in non-contact with the filter paper.

[0092] S6603, move the pipette to the visual inspection mechanism to check whether there is liquid hanging on the outside of the tip; if liquid is detected on the outside of the tip, move the pipette to the wiping mechanism and wipe again until no residual liquid is detected on the wall, and then end the wiping operation.

[0093] Specifically, the drainage operation in S606 is shown in Figure 10 As shown, the gripper moves the pipette to the weighing cup on the balance 10 to perform the discharge operation. The balance used in the embodiment of the present invention is a Mettler mass comparator XPE26C or XPE205, and the upper computer controls the opening of the balance's skylight. The gripper grasps the pipette and extends into the balance. The electric cylinder 22 precisely adjusts the pressing force and presses the pipette knob 14 to the second stop point to discharge the liquid. Specifically, when discharging the liquid, first insert the pipette tip into the balance, slowly press the knob 14 to the first stop point, wait 1 to 2 seconds, and then fully press it to the second stop point. After the discharge is completed, the pipette is removed, and the balance senses that the operation is complete, and the skylight automatically closes. Taking the measurement point of 20μL as an example, when a slow and uniform pressure of 5N is applied to the pipette adjustment knob 14, the knob 14 will move linearly to the first stop point. Because the applied force value does not reach the threshold, the knob 14 cannot overcome the resistance of the internal mechanical structure and continue to move downward. Only when the pressing load increases to 20N can the knob 14 break through the resistance threshold and complete the full stroke movement under continuous pressure drive to reach the second stop point of the mechanical limit, which is the bottom.

[0094] Specifically, in S606, the visual inspection mechanism is used to collect information about residual liquid. Specifically, the pipette is moved to the second camera 81, and the visual inspection module is used to perform a droplet visual inspection to check whether there is any residual liquid in the tip. If residual liquid is detected in the tip, the pipette is moved to the weighing cup and the liquid is re-drained. If residual liquid is still present in the tip after more than three inspections, the tip is replaced and the aspiration and subsequent operations are repeated until it is confirmed that there is no residual liquid in the tip.

[0095] See also Figure 11 Figure 2 shows a schematic diagram of the tip replacement process in an automated pipette calibration method according to an embodiment of the present invention. The gripper 21 moves the pipette to the tip gripper 12. The tip is then slowly moved vertically into the gripper's prongs, whereupon the tip gripper 12 securely grasps the tip. The pipette is then lifted upward, freeing the tip from the pipette base 11 and dropping it into the tip waste bin below, completing the tip separation.

[0096] Specifically, if there are multiple pipettes to be calibrated, in the input step S601, the user numbers the pipettes, enters the numbers and corresponding model information of all pipettes into the host computer, and generates a QR code, which is printed on a sticker and pasted on the corresponding pipette; the host computer calibrates the pipettes in sequence according to the numbers, and the calibration includes the identification step S602 to the judgment step S609.

[0097] During operation of this embodiment, a pipette is manually placed on the pipette holder, and the first camera 61 on the collaborative arm 2 scans the code to identify the corresponding pipette. After the gripper 21 grasps the pipette, it places the appropriate pipette tip 15 on the tip box 4 and moves to the gear shift mechanism 5 for gear shifting. After gear shifting is complete, the pipette is moved to the reservoir 7 filled with distilled water for aspiration. After aspiration is complete, the pipette is moved to the wiping mechanism 9 to wipe any residual liquid around the pipette. The pipette is then moved to the second camera 81 to detect any droplets clinging to the outside of the tip. If no droplets cling to the tip, the pipette is moved to the weighing cup in the balance 10 for drainage. During drainage, the tip is held at a 45° angle, and the electric cylinder 22 presses to drain the liquid. After drainage is complete, the skylight of the balance 10 is closed, and the pipette is moved to the second camera 81 to detect any residual droplets in the tip. If no droplets remain in the tip, the balance 10 reads the measurement data, completing a pipette calibration. Each measuring point needs to be measured repeatedly several times (6 times in the embodiment of the present invention), and the electronic balance difference is recorded. After a record is completed, before measuring again, the suction head 15 is replaced by the suction head clamp 12, and then the pipette is moved to the gear adjustment mechanism 5, the capacity is adjusted to the next measuring point, and the above steps are repeated. Each pipette may have multiple measuring points (3 measuring points in the embodiment of the present invention). After the measurement is completed, the qualified pipette is hung back on the pipette holder 3, and the unqualified pipette is placed in the material box 11, and then the next pipette is clamped from the holder 3 for measurement. This set of pipette automatic calibration system is suitable for a variety of pipettes, and the effect of automatic calibration can be achieved. In actual operation, the host computer can also be set to send the calibration data to the measurement information system in a timely and accurate manner, and prompt the message of calibration completion, thereby significantly improving operating efficiency, reducing human errors, and realizing the automation and informatization of pipette calibration work.

[0098] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A pipette automatic calibration device, characterized in that: include: Pipette holder, used to place pipettes; A collecting mechanism, used for collecting model information of the pipette; a collaborative arm for controlling pipette movement; Tip box, used to place tips; A shifting mechanism for adjusting the volume display of the pipette according to the measuring point; A liquid reservoir, used to contain liquid for calibration; Electric cylinder, used to control the pipette to aspirate or dispense liquid; Wiping mechanism, used to remove droplets hanging on the wall of the suction head; A visual inspection mechanism for confirming the volume display of the pipette and determining whether there is liquid residue in the pipette tip; Tip holder, used to remove the tip from the pipette; A weighing device, used to detect the volume of the liquid discharged by the pipette; The host computer is used to control the operation of the collaborative arm, gear adjustment mechanism, electric cylinder and suction head clamp according to the information sent by the acquisition mechanism and visual detection mechanism.

2. The automatic pipette calibration device according to claim 1, characterized in that: The acquisition mechanism includes a first camera and a sticker printed with a QR code; the sticker is affixed to the pipette body, and the QR code on the sticker includes the model information of the pipette; the first camera is used to acquire the QR code information and send it to the host computer.

3. The automatic pipette calibration device according to claim 1, characterized in that: The gear shifting mechanism includes a driving gear, two driven gears, two rubber wheels, and a drive motor; the gear shifting mechanism fixes the pulley through the two rubber wheels; the drive motor controls the rotation of the driving gear, which drives the two driven gears to rotate, and the two driven gears respectively drive the two rubber wheels to rotate, thereby driving the pulley to rotate and changing the capacity display of the pipette.

4. The automatic pipette calibration device according to claim 1, characterized in that: The wiping mechanism includes a reel, a fixed reel, a drive motor and filter paper; the fixed reel is rigidly fixed to the work surface by a first bracket, and the drive motor is rigidly fixed to the work surface by a second bracket; the rolled filter paper is sleeved on the fixed reel, and the free end of the filter paper is drawn out from the fixed reel and wrapped around the outer circumference of the reel, so that the filter paper between the reel and the fixed reel is in a tensioned and straightened state; the drive motor is used to drive the rotating reel to rotate, and the wiped filter paper segment is rolled into the reel for storage, and at the same time, the tightening force of the filter paper is used to drive the filter paper roll on the fixed reel to rotate, so that a new unused filter paper segment is drawn out from the front end of the fixed reel.

5. The automatic pipette calibration device according to claim 1, characterized in that: The visual detection mechanism includes a second camera and a visual detection module, the second camera is used to capture images, and the visual detection module is used to make judgments based on the images captured by the second camera; This includes the following situations: The second camera captures an image of the pipette's capacity display, and the visual detection module determines the current value of the capacity display; The second camera captures an image of the pipette tip, and the visual inspection module determines whether there is liquid attached to the outside of the tip; The second camera captures the image of the pipette tip, and the visual inspection module determines whether there is any liquid residue inside the tip.

6. A method for automatic calibration of a pipette, characterized in that: The automatic pipette calibration device according to any one of claims 1 to 4 comprises the following steps: In the input step, the user enters the model information of the pipette to be calibrated into the host computer, and affixes the QR code sticker containing the model information to the pipette gun body, and finally places the pipette on the pipette holder; In the identification step, the collection mechanism collects the model information of the pipette and uploads it to the host computer; the host computer confirms the pipette model, sets the measurement point according to the pipette model, and controls the collaborative arm to clamp the pipette; Preparation step: Move the pipette to the tip box and put on the appropriate tip, then move it to the adjustment mechanism and adjust the pipette volume display to the measurement point; In the liquid aspiration step, the pipette is moved to the liquid reservoir and the pipette is controlled by the electric cylinder to aspirate the liquid; In the wiping step, filter paper is used to remove the liquid on the pipette tip. Then, the visual detection mechanism is used to collect the liquid residual information of the pipette tip to determine whether there is still liquid on the outside of the pipette tip. If so, the wiping step is performed again. Otherwise, the liquid discharge step is entered. In the liquid discharge step, the pipette is moved to the weighing device, and the electric cylinder presses the knob of the pipette to control the pipette to discharge liquid; the visual detection mechanism is used to collect liquid residual information to determine whether there is liquid residual in the tip. If so, the liquid is discharged again, otherwise the first repetition step is entered; The first repeating step is to keep the measuring point unchanged, repeat the preparation step to the discharge step several times, record the difference between the weighing data of each weighing machine and the weighing data of multiple weighing machines, and complete the calibration of the measuring point; The second repetition step changes the measuring point and repeats the preparation step to the first repetition step several times to complete the calibration of multiple measuring points; The judgment step is to judge whether the pipette is qualified according to the calibration results of each measurement point.

7. The automatic pipette calibration method according to claim 6, characterized in that: The shifting mechanism adjusts the volume display of the pipette to the measuring point, comprising the following steps: The cooperative arm moves the pipette to the gear-shifting mechanism so that its pulley is fixed between the two rubber wheels of the gear-shifting mechanism, and then releases the pipette; The drive motor of the gear adjustment mechanism controls the rotation of the driving gear, which drives the pulley to rotate, thereby changing the volume display of the pipette; The visual inspection mechanism records the pipette's capacity display in real time and uploads it to the host computer. When the capacity reaches the required measurement point, the host computer controls the gear adjustment mechanism to stop rotating; The cooperative arm re-grips the pipette and moves the pulley of the pipette out from between the two rubber wheels of the gear adjustment mechanism.

8. The automatic pipette calibration method according to claim 6, characterized in that: The wiping step comprises the following steps: Move the pipette to the wiping mechanism and hold the pipette vertically; Use the multiple-touch method to wipe. Each time you touch, move the pipette to the side of the filter paper, positioning the tip of the pipette 2 to 3 mm below the surface of the stretched filter paper. Then, move the pipette horizontally at a constant speed until the outer edge of the tip touches the edge of the filter paper, ensuring that the tip of the pipette is always in non-contact with the filter paper. Move the pipette to the visual inspection mechanism to check whether there is liquid hanging on the outside of the tip; if liquid is detected on the outside of the tip, move the pipette to the wiping mechanism and wipe again until no residual liquid is detected on the wall, and then end the wiping operation.

9. The automatic pipette calibration method according to claim 6, characterized in that: The drainage step comprises the following steps: Move the pipette to the weighing machine and insert the pipette tip into the weighing cup inside the weighing machine; Adjust the pressing force of the electric cylinder, press the knob to the first stop, wait 1 to 2 seconds, and then press the button fully to the second stop; Move the pipette to the visual inspection mechanism for droplet visual inspection to check whether there is any liquid residue in the tip; If residual liquid is detected in the tip, the pipette is moved to the weighing cup and the liquid is discharged again until it is confirmed that there is no liquid residual in the tip, and the discharge operation is ended; if residual liquid is still detected in the tip after the Kth discharge, the tip on the pipette is removed by the tip clamp, the pipette is moved to the tip box and a new tip is put on, and then the pipette is returned to the aspiration step; K times is the preset threshold.

10. The automatic pipette calibration method according to claim 5, characterized in that: If there are multiple pipettes to be calibrated, in the input step, the user numbers the pipettes, generates a QR code using the numbers and corresponding model information of all the pipettes, pastes the codes to the corresponding pipettes respectively, and finally inputs the numbers and corresponding model information into the host computer; the host computer calibrates the pipettes in sequence according to the numbers, and the calibration includes the identification step to the judgment step.

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