A plug movement and liquid flow rate control device for a positive pressure solid phase extractor and a method of using the same

Abstract

The present invention belongs to the technical field of inspection devices, and particularly relates to a plug movement and liquid flow rate control device for a positive pressure solid phase extractor and a method for using the device, comprising a plurality of micro servo electric cylinders, wherein the lower end of the telescopic shaft of each micro servo electric cylinder is fixed with a quick connector, a pressure sensor, a connecting plate, and an elastic plunger in sequence, the extraction column is directly below the elastic plunger, the extraction column is mounted on a fixed plate B, the micro servo electric cylinder is mounted on a fixed plate A, a measuring cup is placed directly below the extraction column outlet, the measuring cup is placed on a micro high-precision weighing sensor, and each electronic control component is connected to a display PLC controller by wire or wirelessly. When a certain pressure sensor reaches the upper limit value, the servo electric cylinder stops working. The device solves the problem of controlling the liquid flow rate at the extraction column outlet, and also solves the problem of "blockage" of individual extraction columns affecting the operation of other plugs, effectively improving the quality and efficiency of detection.

Description

Technical Field

[0001] The invention belongs to the technical field of testing devices, and in particular relates to a plug movement and liquid flow rate control device for a positive pressure solid phase extractor and a use method thereof. Background Art

[0002] Solid-phase extraction (SPE) is a sample pretreatment step during the testing process. It uses solid adsorbents to adsorb the target compound in the liquid sample and separate it from the sample matrix and interfering compounds. The target compound is then eluted with an eluent or desorbed by heating to achieve the purpose of separating and enriching the target compound. There are two types of SPE devices: positive pressure and negative pressure. Positive pressure SPE devices use air as the power source to pass through the SPE column, while negative pressure SPE devices use vacuum negative pressure as the power source to pass through the SPE column. SPE columns are mostly syringe-type polypropylene tubes with an adsorbent filler sieve plate installed at the bottom of the column. The top of the SPE column is open, and the liquid passes through the adsorbent filler sieve plate and is discharged from the lower end of the extraction column. Positive pressure SPE is a process in which the plunger rod is vertically inserted into the extraction column and the sample liquid is discharged from the lower end of the extraction column through the adsorbent sieve plate using positive air pressure. There are strict requirements on the speed at which the liquid flows out of the outlet. If the flow rate does not meet the requirements, impurities and other substances will not be filtered thoroughly, affecting the determination of the target substance content. Although the extractor can set the descending speed of the plunger rod in the extraction column, it still cannot ensure the outlet liquid flow rate. The reason is that the reaction of each individual sample liquid through the adsorbent filler sieve plate is different, and the plunger rods of the conventional positive pressure solid phase extractor currently used move downward in rows at the same speed. The outlet liquid flow rate of each extraction column cannot be effectively controlled. Sometimes, the sample liquid in individual extraction columns will cause blockage when passing through the adsorbent filler sieve plate, resulting in the inability of the entire row of plunger rods to move downward, which further reduces the detection quality and efficiency.

[0003] Purpose of the Invention

[0004] To remedy the shortcomings of the existing technology, the present invention provides a plug movement and liquid flow rate control device for a positive pressure solid phase extractor, which can control the flow rate of the liquid at the outlet of each extraction column. At the same time, the occurrence of "blockage" will not affect the movement of other plugs, thereby achieving the purpose of improving detection quality and efficiency. Summary of the Invention

[0005] The present invention is achieved through the following technical solutions:

[0006] A plug column movement and liquid flow rate control device for a positive pressure solid phase extractor, comprising a micro servo electric cylinder; a telescopic shaft of the micro servo electric cylinder moves up and down in an extraction column;

[0007] A quick connector is installed at the lower end of the telescopic shaft of the micro servo electric cylinder, a pressure sensor is installed at the lower end of the quick connector, a connecting plate is installed at the lower end of the pressure sensor, and an elastic plunger is fixed at the lower end of the connecting plate;

[0008] A measuring cup is provided just below the outlet of the lower end of the extraction column, and the measuring cup is placed on a micro high-precision weighing sensor.

[0009] Preferably, the plug movement and liquid flow rate control device of the positive pressure solid phase extractor also includes a fixed plate A and a fixed plate B, and the fixed plate A is located below the fixed plate B; a plurality of the micro servo electric cylinders are installed on the fixed plate A, and a plurality of the extraction columns are installed on the fixed plate B below the micro servo electric cylinder.

[0010] Preferably, the electric control wires of the micro servo electric cylinder and the micro high-precision weighing sensor are connected to the display PLC controller in a wired or wireless manner.

[0011] Preferably, an adsorbent filler sieve plate is provided at the lower portion of the extraction column, sample liquid A is injected above the adsorbent filler sieve plate, and compressed air is present between the liquid surface of the sample liquid A and the elastic plunger.

[0012] The method for using the plug movement and liquid flow rate control device of the positive pressure solid phase extractor is characterized by:

[0013] S1. Inject sample liquid A into each extraction column and press the working button on the PLC controller to put all electronic control components into operation. Each micro high-precision weighing sensor automatically records the total mass of the measuring cup and transmits the weighing data to the PLC controller in real time.

[0014] S2, the working telescopic shaft of each micro servo electric cylinder moves downward rapidly, and when the elastic plunger enters the extraction column, it decelerates and moves downward at the programmed speed. The lower surface of the elastic plunger pushes the compressed air to press down the liquid A surface. The liquid A is driven by the pressure to pass through the adsorbent filler sieve plate and fall into the measuring cup (3) through the outlet in the form of droplets. The falling droplets gradually increase the mass of the liquid B in the measuring cup, and the rate of increase is transmitted in real time by the micro high-precision weighing sensor to the display PLC controller;

[0015] S3. When the rate of increase of the mass transmitted by a micro high-precision load cell is about to exceed the upper limit, the PLC controller controls the micro servo electric cylinder corresponding to the micro high-precision load cell to slow down the downward movement of the telescopic shaft and the frequency of the droplet falling, so that the rate of increase of the weighing mass of the micro high-precision load cell returns to the programmed set value;

[0016] S4. When the rate of increase of the mass transmitted by a micro high-precision load cell is about to fall below the lower limit, the PLC controller controls the micro servo electric cylinder corresponding to the micro high-precision load cell to increase the speed of operation, so that the telescopic shaft moves downward faster, the droplet falling frequency becomes faster, and the rate of increase of the weighing mass of the micro high-precision load cell returns to the programmed set value, thereby ensuring the flow rate of the droplets at the outlet of the extraction column;

[0017] S5. When the rate of increase of the mass transmitted by a micro high-precision weighing sensor is about to fall below the lower limit, the PLC controller controls the micro servo electric cylinder corresponding to the micro high-precision weighing sensor to increase the speed of operation to accelerate the downward movement of the telescopic shaft. If the pressure sensor increase value exceeds the programmed set value, the PLC controller controls the micro servo electric cylinder to stop working. At this time, it indicates that a blockage has occurred between the liquid A in the extraction column and the adsorbent filler sieve plate.

[0018] Beneficial technical effects of the present invention:

[0019] The present invention includes components such as plunger transmission and pressure control, liquid flow rate quality monitoring, and a display PLC controller. Each plunger rod is powered by a separate micro-servo electric cylinder. The electrical control leads of each micro-servo electric cylinder and micro-high-precision load cell are connected to the display PLC controller via wired or wireless connections. The PLC controller is fed with a control program and a self-learning adaptive program. For example, the PLC controls the micro-servo electric cylinder to maintain the permissible range of the rate of increase in the force generated by the micro-high-precision load cell due to the droplet's falling frequency. The micro-servo electric cylinder stops operating when the pressure sensor's increase reaches a set value.

[0020] This invention solves the problem in conventional extractors where rows of plug rods can only be lowered simultaneously and cannot be controlled individually. The plug rods in the present invention can be moved individually or simultaneously and can be controlled individually. This solves the problem in conventional extractors where the outlet liquid flow rate could not be effectively controlled, achieving quantitative control of the outlet flow rate (flow rate). BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The structural features and usage of the present invention are further described with reference to the accompanying drawings:

[0022] Figure 1 It is a main sectional view of the present invention;

[0023] Figure 2 yes Figure 1 of Enlarged view of the department;

[0024] Figure 3 It is the control principle diagram;

[0025] Figure: 1. Workbench surface, 2. Micro high-precision weighing sensor, 3. Measuring cup, 4. Display PLC controller, 5. Extraction column, 6. Telescopic shaft, 7. Micro servo electric cylinder, 8. Fixing plate A, 9. Fixing plate B, 10. Liquid B, 11. Adsorbent filler sieve plate, 12. Liquid A, 13. Compressed air, 14. Elastic plunger, 15. Quick connector, 16. Pressure sensor, 17. Connecting plate. DETAILED DESCRIPTION

[0026] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0027] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless otherwise clearly indicated in the present invention, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "include" and / or "comprising" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations;

[0028] For the convenience of description, if the words "up", "down", "left" and "right" appear in the present invention, they only indicate that they are consistent with the up, down, left and right directions of the drawings themselves, and do not limit the structure. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, they cannot be understood as limiting the present invention.

[0029] Explanation of terms: The terms "install", "connect", "connect", "fix" and the like in the present invention should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral whole; it can be a mechanical connection or an electrical connection, a direct connection, or an indirect connection through an intermediate medium, an internal connection between two elements, or an interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0030] Figures 1 to 3 This is one of the embodiments of the present invention.

[0031] A plug movement and liquid flow rate control device for a positive pressure solid phase extractor includes a fixed plate A8 and a fixed plate B9, wherein the fixed plate A8 is located below the fixed plate B9; a plurality of micro servo electric cylinders 7 are mounted on the fixed plate A8, and a plurality of extraction columns 5 are mounted on the fixed plate B9 below the micro servo electric cylinders 7.

[0032] The power of the plunger rod in a single extraction column 5 is provided by a single micro servo electric cylinder 7. The lower end of the telescopic shaft 6 of the micro servo electric cylinder 7 is equipped with a quick connector 15, the lower end of the quick connector 15 is equipped with a pressure sensor 16, the lower end of the pressure sensor 16 is equipped with a connecting plate 17, and the lower end of the connecting plate 17 is fixed with an elastic plunger.

[0033] A measuring cup 3 is provided just below the outlet of the lower end of the extraction column 5. The measuring cup 3 is placed on a micro high-precision weighing sensor 2. The micro high-precision weighing sensor 2 is placed on a workbench surface 1. Figure 1 .

[0034] The extraction column 5 is provided with an adsorbent filler sieve plate 11 at the bottom. The sample liquid A12 is injected above the adsorbent filler sieve plate 11. Compressed air 1316 is stored between the liquid surface of the sample liquid A12 and the elastic plunger. Figure 2 .

[0035] The electrical control wires of each micro-servo electric cylinder 7 and micro-high-precision load cell 2 are connected to a display PLC controller 4, either wired or wirelessly. A control program and a self-learning adaptive program are input into the PLC controller. For example, the PLC controller controls the micro-servo electric cylinder 7 to maintain the allowed range of the rate of increase in the force generated by the micro-high-precision load cell 2 according to the droplet's falling frequency. When the pressure sensor 16's increase reaches a set value, the micro-servo electric cylinder 7 stops operating.

[0036] The method of using the present invention is as follows: after the sample liquid A12 is injected into each extraction column 5, the working button in the PLC controller 4 is pressed, and each electronic control component enters the working state. Each micro high-precision load cell 2 automatically records the total mass of the measuring cup 3 and transmits the weighing data to the PLC controller in real time. Each micro servo electric cylinder 7 causes the telescopic shaft 6 to move downward rapidly. After the elastic plunger enters the extraction column 5, it decelerates and moves downward at a programmed speed. The lower surface of the elastic plunger pushes the compressed air 13 downward, depressing the level of liquid A 12. Driven by the pressure below, liquid A 12 passes through the adsorbent filler sieve plate 11 and falls into the measuring cup 3 through the outlet in the form of droplets. The falling droplets gradually increase the mass of liquid B 10 in the measuring cup 3. The rate of increase is transmitted in real time by the micro high-precision load cells 2 to the PLC controller 4 for display. When the rate of increase of the mass transmitted by a micro high-precision load cell 2 is about to exceed the upper limit, the PLC controller controls the micro servo electric cylinder 7 corresponding to that micro high-precision load cell 2 to slow down the downward movement of the telescopic shaft 6, slow the frequency of the droplets falling, and return the rate of increase of the weighing mass of that micro high-precision load cell 2 to the programmed value. Similarly, when the rate of increase of the mass transmitted by a certain micro high-precision weighing sensor 2 is about to fall below the lower limit, the PLC controller controls the corresponding micro servo electric cylinder 7 above the micro high-precision weighing sensor 2 to increase its speed so that the telescopic shaft 6 moves downward faster, the droplet falling frequency becomes faster, and the rate of increase of the weighing mass of the micro high-precision weighing sensor 2 returns to the programmed set value. This ensures the flow rate of the droplets at the outlet of the extraction column 5. When the rate of increase of the mass transmitted by a certain micro high-precision weighing sensor 2 is about to fall below the lower limit, the PLC controller controls the corresponding micro servo electric cylinder 7 above the micro high-precision weighing sensor 2 to increase its speed so that the telescopic shaft 6 moves downward faster. If the increase value of the pressure sensor 16 exceeds the programmed set value, the PLC controller controls the micro servo electric cylinder 7 to stop working. This indicates that a blockage has occurred between the liquid A12 in the extraction column 5 and the adsorbent filler sieve plate 11. See attached figure. Figure 1 .

[0037] The present invention solves the problem of controlling the liquid flow rate at the outlet of the extraction column 5 and also solves the problem of "clogging" of individual extraction columns 5 affecting the operation of other extraction columns, thereby effectively improving the detection quality and efficiency.

[0038] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A plug movement and liquid flow rate control device for a positive pressure solid phase extractor, characterized in that: It comprises a micro servo electric cylinder (7); the telescopic shaft (6) of the micro servo electric cylinder (7) moves up and down in the extraction column (5); A quick connector (15) is installed at the lower end of the telescopic shaft (6) of the micro servo electric cylinder (7), a pressure sensor (16) is installed at the lower end of the quick connector (15), a connecting plate (17) is installed at the lower end of the pressure sensor (16), and an elastic plunger is fixed at the lower end of the connecting plate (17); when the increase value of the pressure sensor (16) reaches a set value, the micro servo electric cylinder (7) stops working; An adsorbent filler sieve plate (11) is provided at the lower portion of the extraction column (5), a sample liquid A (12) is injected above the adsorbent filler sieve plate (11), and compressed air (13) is stored between the liquid surface of the sample liquid A (12) and the elastic plunger; A measuring cup (3) is provided just below the outlet of the lower end of the extraction column (5), and the measuring cup (3) is placed on a micro high-precision weighing sensor (2); The electric control wires of the micro servo electric cylinder (7) and the micro high-precision weighing sensor (2) are connected to the display PLC controller (4) in a wired or wireless manner; a control program and a self-learning adaptive program are input into the PLC controller (4) to control the micro servo electric cylinder (7) and the micro high-precision weighing sensor (2).

2. The plug movement and liquid flow rate control device for a positive pressure solid phase extractor according to claim 1, characterized in that: It also includes a fixed plate A (8) and a fixed plate B (9), wherein the fixed plate A (8) is located below the fixed plate B (9); a plurality of the micro servo electric cylinders (7) are mounted on the fixed plate A (8), and a plurality of the extraction columns (5) are mounted on the fixed plate B (9) below the micro servo electric cylinders (7).

3. A method for using the plug movement and liquid flow rate control device of the positive pressure solid phase extractor according to claim 2, characterized in that: S1. Inject the sample liquid A (12) into each extraction column (5), press the working button in the display PLC controller (4), and each electronic control component enters the working state; each micro high-precision weighing sensor (2) automatically records the total mass of the measuring cup (3) and transmits the weighing data to the PLC controller (4) in real time; S2, the working telescopic shaft (6) of each micro servo electric cylinder (7) moves downward rapidly, and when the elastic plunger enters the extraction column (5), it decelerates and moves downward at a programmed speed. The lower surface of the elastic plunger pushes the compressed air (13) to press down the liquid surface of liquid A (12). The liquid A (12) is driven by the pressure below to pass through the adsorbent filler sieve plate (11) and fall into the measuring cup (3) through the outlet in the form of droplets. The falling droplets gradually increase the mass of liquid B (10) in the measuring cup (3), and the rate of increase is transmitted in real time by the micro high-precision weighing sensor (2) to the display PLC controller (4); S3. When the rate of increase of the mass transmitted by a certain micro high-precision weighing sensor (2) is about to exceed the upper limit value, the PLC controller (4) controls the micro servo electric cylinder (7) corresponding to the micro high-precision weighing sensor (2) to slow down the movement of the telescopic shaft (6) and the frequency of the droplet falling, so that the rate of increase of the weighing mass of the micro high-precision weighing sensor (2) returns to the programmed set value; S4. When the rate of increase of the mass transmitted by a certain micro high-precision weighing sensor (2) is about to fall below the lower limit, the PLC controller (4) controls the micro servo electric cylinder (7) corresponding to the micro high-precision weighing sensor (2) to increase the speed of operation so that the telescopic shaft (6) moves downward faster, the droplet falling frequency becomes faster, and the rate of increase of the weighing mass of the micro high-precision weighing sensor (2) returns to the programmed set value, thereby ensuring the flow rate of the droplets at the outlet of the extraction column (5); S5. When the rate of increase of the mass transmitted by a certain micro high-precision weighing sensor (2) is about to fall below the lower limit, the PLC controller (4) controls the micro servo electric cylinder (7) corresponding to the micro high-precision weighing sensor (2) to increase the speed of operation so that the telescopic shaft (6) moves downward faster. If the increase value of the pressure sensor (16) exceeds the programmed set value, the PLC controller (4) controls the micro servo electric cylinder (7) to stop working. At this time, it indicates that a blockage has occurred between the liquid A (12) in the extraction column (5) and the adsorbent filler sieve plate (11).

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