Automatic calibration device for peristaltic pump in automatic acid adding instrument

Abstract

An automatic calibration device for a peristaltic pump in an automatic acid dispensing apparatus includes a reagent station equipped with a weighing sensor and a temperature sensor, the weighing sensor supporting a reagent bottle; a test tube rack holding test tubes to be dispensed; a robotic arm positioned above one side of the test tube rack; a waste liquid tank positioned below one side of the robotic arm; and a peristaltic pump, the inlet of which is connected to the reagent bottle, and the outlet of which is installed at the moving end of the robotic arm. This invention, by using a weighing sensor to weigh the reagent bottle and a temperature sensor to detect the temperature of the reagent's environment, can accurately calculate the volume corresponding to the mass of liquid extracted from the reagent bottle. It can calibrate the pumping parameters of the peristaltic pump, improving dispensing accuracy, saving reagents, reducing labor costs, and detecting equipment malfunctions early.

Description

Technical Field

[0001] This utility model relates to the field of chemistry, and more particularly to an automatic acid adder, especially an automatic calibration device for a peristaltic pump in an automatic acid adder. Background Technology

[0002] In existing technologies, the peristaltic pumps in automated acid dispensers rely on manual calibration, such as calibration using standard containers or indirect volume measurement using level sensors. However, because the performance of peristaltic pumps is affected by factors such as pump tube temperature, aging, and changes in reagent viscosity, traditional methods cannot achieve dynamic calibration, requiring frequent manual intervention, resulting in low efficiency and a poor user experience. Current automated acid dispensers require cleaning and filling the tubing with the new target reagent before the first dispensing and before switching reagents to ensure the accuracy of subsequent dispensing volumes; however, there is currently no technology that integrates the tubing cleaning process with real-time parameter correction.

[0003] In the prior art, utility model patent CN114870922B discloses a fully automatic acid dosing device. It uses at least two sets of liquid level sensors in the constant volume chamber of an automatic calibration tank, with the bottom of the constant volume chamber connected to the dosing chamber. When the liquid level reaches the first set of liquid level sensors, it triggers the counting of peristaltic pump rotations and timing. When the liquid level reaches the other set of liquid level sensors, it can count the total number of peristaltic pump rotations and the dosing time during this heating process, thus automatically calculating the dosing volume per rotation and the dosing speed, enabling automatic calibration upon startup. However, this solution does not consider the influence of reagent viscosity. There may be a time difference between the reagent dripping from the dosing port into the dosing chamber and the rise in liquid level in the constant volume chamber, affecting calibration accuracy. After calibration, the reagent in the calibration tank can only be discharged as waste, wasting the reagent. Utility Model Content

[0004] The purpose of this utility model is to provide an automatic calibration device for the peristaltic pump in an automatic acid adder. This automatic calibration device for the peristaltic pump in an automatic acid adder aims to solve the technical problems of calibration lag and waste of calibration solution in the prior art.

[0005] The automatic calibration device for the peristaltic pump in the automatic acid dosing apparatus of this invention includes:

[0006] A reagent station, wherein the reagent station is equipped with a weighing sensor and a temperature sensor, and the weighing sensor supports a reagent bottle;

[0007] A test tube rack, wherein test tubes to be added with liquid are placed;

[0008] A robotic arm, which is positioned above one side of the test tube rack;

[0009] Waste liquid tank, which is located below one side of the robotic arm;

[0010] A peristaltic pump, wherein the inlet of the pump tube is connected to a reagent bottle, and the outlet is installed at the moving end of a robotic arm;

[0011] The controller has its input terminal electrically connected to the output terminals of the weighing sensor and the temperature sensor, and its output terminal electrically connected to the control terminal of the peristaltic pump and the control terminal of the robotic arm.

[0012] Furthermore, the reagent station is equipped with multiple weighing sensors, and multiple reagent bottles are placed on the weighing sensors. Each reagent bottle is connected to one input terminal of a switching valve. The output terminal of the switching valve is connected to the input terminal of the peristaltic pump, and the control terminal of the switching valve is electrically connected to the output terminal of the controller.

[0013] Furthermore, it also includes a human-computer interaction device, which includes a touch screen that is connected to the controller via a communication channel and is used to input and display control information.

[0014] Furthermore, the lower end of the waste liquid tank is connected to a waste liquid bucket via a pipeline.

[0015] Compared with existing technologies, the advantages of this invention are positive and significant. By using a weighing sensor to weigh the reagent bottle and a temperature sensor to detect the temperature of the reagent's environment, this invention can accurately calculate the volume corresponding to the mass of liquid extracted from the reagent bottle. It can also calibrate the pumping parameters of the peristaltic pump, improve dispensing accuracy, save reagents, reduce labor costs, and detect equipment malfunctions earlier. Attached Figure Description

[0016] Figure 1 This is a top view schematic diagram of the structure of this utility model.

[0017] Figure 2 This is a cross-sectional schematic diagram of the reagent station of this utility model.

[0018] Figure 3 This is a block diagram of the control structure of this utility model.

[0019] The markings in the diagram are: 1. Reagent station; 101. Reagent bottle; 102. Weighing sensor; 103. Temperature sensor; 2. Switching valve; 3. Peristaltic pump; 301. Liquid outlet; 4. Robotic arm; 5. Test tube rack; 501. Test tube to be added; 6. Waste liquid tank; 7. Waste liquid bucket; 8. Controller; 9. Human-machine interface device. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this does not limit the present invention.

[0021] like Figure 1-3 As shown, the automatic calibration device for the peristaltic pump in an automatic acid dosing apparatus of this utility model includes:

[0022] Reagent station 1 is equipped with a weighing sensor 102 and a temperature sensor 103. The weighing sensor 102 supports a reagent bottle 101.

[0023] Test tube rack 5, wherein test tube rack 5 holds test tubes 501 to be added with liquid;

[0024] Robotic arm 4, which is positioned above one side of the test tube rack 5;

[0025] Waste liquid tank 6 is located below one side of the robotic arm 4;

[0026] The peristaltic pump 3 has its inlet connected to the reagent bottle 101 and its outlet 301 installed at the moving end of the robotic arm 4.

[0027] The controller 8 has its input terminal electrically connected to the output terminal of the weighing sensor 102 and the output terminal of the temperature sensor 103, and its output terminal electrically connected to the control terminal of the peristaltic pump 3 and the control terminal of the robotic arm 4.

[0028] Furthermore, the reagent station is equipped with multiple weighing sensors, and multiple reagent bottles are placed on the weighing sensors. Each reagent bottle is connected to one input terminal of a switching valve. The output terminal of the switching valve is connected to the input terminal of the peristaltic pump, and the control terminal of the switching valve is electrically connected to the output terminal of the controller.

[0029] Furthermore, it also includes a human-computer interaction device, which includes a touch screen that is connected to the controller via a communication channel and is used to input and display control information.

[0030] Furthermore, the lower end of the waste liquid tank is connected to a waste liquid bucket via a pipeline.

[0031] The method of using this utility model is as follows:

[0032] S1. Before adding the target reagent, use the peristaltic pump 3 to draw the target reagent from the reagent bottle 101 and fill the upstream pipeline before the peristaltic pump 3.

[0033] Specifically, in this step, "before adding the target reagent" can refer to the operation of filling the tubing before the first addition of reagent after power-on, or it can refer to the operation of cleaning the tubing after switching to the target reagent via switching valve 3 after adding the previous reagent. This can drive the peristaltic pump 3 to draw a certain amount of the target reagent to fill the upstream tubing before the peristaltic pump 3, ensuring that all the peristaltic pump 3 pumps during subsequent calibration is the target reagent, and avoiding the impact of residual previous reagent in the pumping tubing on calibration accuracy.

[0034] S2. Weigh the mass M1 of reagent bottle 101 at this time, and make peristaltic pump 3 work for a time period T_1, where T_1 = V_set × K_old, where V_set represents the volume of liquid required to fill the entire tubing with the target reagent, K_old represents the calibration coefficient when the reagent was used last time, and K_old is the time required for peristaltic pump 3 to pump each milliliter of reagent.

[0035] Specifically, in this step, the mass M1 of reagent bottle 101 is first weighed using weighing sensor 102. Then, peristaltic pump 3 is started to pump the target reagent volume V_set and fill the entire tubing. Calibration is completed while cleaning the tubing to avoid adding the previous reagent during subsequent liquid additions. V_set is a slightly larger volume than the volume used to fill the entire tubing, ensuring that the target reagent fills the entire tubing during cleaning. Based on the calibration parameter K_old of the previous pumping of the same reagent, the working time T_1 required for peristaltic pump 3 to pump V_set can be calculated. Peristaltic pump 3 maintains a constant speed. The calibration parameter represents the time required for peristaltic pump 3 to pump each milliliter of reagent.

[0036] S3. Weigh the mass M2 of reagent bottle 101 at this time, and calculate the mass of reagent discharged from reagent bottle 101, ΔM = |M1-M2|.

[0037] Specifically, in this step, the mass M2 of reagent bottle 101 after the peristaltic pump 3 pumps the reagent for time period T_1 is weighed, and the mass ΔM of the discharged reagent is calculated.

[0038] S4. Calculate the actual volume V_actual = ΔM / ρ corresponding to the mass ΔM of the reagent discharged from reagent bottle 101, where ρ represents the density of the target reagent at the current temperature.

[0039] Specifically, the reagent density changes with temperature. This step can accurately calculate the actual volume V_actual corresponding to the discharged mass ΔM based on the density formula. The density of the target reagent under various temperature conditions is provided in advance by the reagent manufacturer and stored in the reagent database.

[0040] S5. Calculate the new calibration coefficient K_new=K_old×(V_set / V_actual)

[0041] Specifically, this step corrects the original calibration coefficient K_old based on the ratio of V_set to V_actual, and the calculated new calibration coefficient K_new is used to replace the original calibration coefficient K_old, so that the new calibration coefficient K_new is more in line with the current temperature and the working state of the peristaltic pump 3.

[0042] S6. Make the peristaltic pump 3 work for a time period of T_2, T_2=V_aim×K_new, and add the target reagent to the test tube 501 to be added, where V_aim represents the volume of the target reagent;

[0043] Specifically, this step can calculate the time T2 required for the peristaltic pump 3 to add the target liquid volume V_aim based on the new calibration coefficient K_new and the target liquid volume V_aim. This allows for accurate quantitative addition of subsequent reagents to the test tube 501. Cleaning and filling the tubing with the target reagent is a necessary operation before each reagent change. The above-mentioned method of this invention can be used for calibration each time a reagent is changed, improving the accuracy of the addition and saving reagents.

[0044] The units for V_set and V_actual mentioned above are ml, the units for M1, M2 and ΔM are g, the unit for ρ is g / ml, the units for K_new and K_old are ms / ml, and the units for T_1 and T_2 are ms.

Claims

1. An automatic calibration device for a peristaltic pump in an automatic acid dosing apparatus, characterized in that, include: A reagent station, wherein the reagent station is equipped with a weighing sensor and a temperature sensor, and the weighing sensor supports a reagent bottle; A test tube rack, wherein test tubes to be added with liquid are placed; A robotic arm, which is positioned above one side of the test tube rack; Waste liquid tank, which is located below one side of the robotic arm; A peristaltic pump, wherein the inlet of the pump tube is connected to a reagent bottle, and the outlet is installed at the moving end of a robotic arm; The controller has its input terminal electrically connected to the output terminals of the weighing sensor and the temperature sensor, and its output terminal electrically connected to the control terminal of the peristaltic pump and the control terminal of the robotic arm.

2. The automatic calibration device for the peristaltic pump in the automatic acid dosing apparatus as described in claim 1, characterized in that: The reagent station is equipped with multiple weighing sensors, and multiple reagent bottles are placed on the weighing sensors. Each reagent bottle is connected to one input terminal of a switching valve. The output terminal of the switching valve is connected to the input terminal of a peristaltic pump, and the control terminal of the switching valve is electrically connected to the output terminal of a controller.

3. The automatic calibration device for the peristaltic pump in the automatic acid dosing apparatus as described in claim 1, characterized in that: It also includes a human-computer interaction device, which includes a touch screen that is connected to the controller via a communication channel and is used to input and display control information.

4. The automatic calibration device for the peristaltic pump in the automatic acid dosing apparatus as described in claim 1, characterized in that: The lower end of the waste liquid tank is connected to a waste liquid bucket via a pipeline.

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