A trace uranium analyzer

Abstract

This invention provides a trace uranium analyzer, comprising a main body, an ultraviolet light source, a detector, and a reagent injection system. The main body has a sample chamber. The reagent injection system includes a pump, a reagent container, and an injection head. The input end of the pump is connected to the reagent container via an input line, and the output end is connected to the injection head via an output line, for dripping reagents into a quartz cuvette within the sample chamber. This invention features a high degree of automation, ensures analytical accuracy, and reduces direct contact between personnel and samples, thus enhancing safety and reliability.

Description

Technical Field

[0001] This invention relates to the field of detection instrument technology, and in particular to a trace uranium analyzer. Background Technology

[0002] The trace uranium analyzer is a specialized optoelectronic instrument used to detect trace uranium content in test samples in fields such as nuclear industry, radiation protection, and scientific research. This instrument uses a stable ultraviolet pulsed light source. During sample testing, a uranium fluorescence enhancer must be manually added to the sample to form a single uranyl ion complex. Upon exposure to pulsed light, this complex is excited to produce a fluorescence signal of a specific wavelength, which is then received by the detector. The intensity of the fluorescence signal reflects the uranium content.

[0003] The analytical methods and procedures of this instrument must comply with relevant national industry standards. Existing trace uranium analyzers require operators to manually place the quartz cuvette containing the sample into the instrument for testing. During the measurement process, the sample chamber must be manually opened twice to add fluorescence enhancers and standard uranium ion solutions, among other detection reagents. Besides being time-consuming, the frequent manual additions of reagents place high demands on operators, making it difficult to guarantee analytical precision. Furthermore, uranium-containing solutions have specific radioactive contamination properties, and fluorescence enhancers are also somewhat toxic; prolonged and frequent direct contact with these substances can pose health risks to operators. Summary of the Invention

[0004] The purpose of this invention is to provide a trace uranium analyzer to solve at least one of the aforementioned technical problems existing in the prior art.

[0005] To solve the above-mentioned technical problems, the present invention provides a trace uranium analyzer, comprising: a main body, an ultraviolet light source, a detector (or detection device), and a detection reagent injection system;

[0006] The main body is provided with a sample chamber;

[0007] The reagent injection system includes an injection pump, a reagent container, and an injection head;

[0008] The input end of the injection pump is connected to the reagent container via an input pipeline, and the output end of the injection pump is connected to the injection head via an output pipeline, for dripping reagents into the quartz cuvette in the sample chamber.

[0009] Furthermore, the detection reagent injection system includes a fluorescence enhancer injection system and a standard uranium liquid injection system;

[0010] The fluorescence enhancer injection system includes a first injection head, a first injection pump, and a first container connected in sequence via pipelines;

[0011] A standard uranium liquid injection system includes a second injection head, a second injection pump, and a second container connected in sequence via pipelines.

[0012] Furthermore, it also includes a first delivery mechanism for extending the injection head into the sample chamber from the outside.

[0013] Furthermore, an opening is provided above the sample chamber for the injection head to extend and retract; the first conveying mechanism is a lifting mechanism, and the injection head is located on the telescopic end of the lifting mechanism.

[0014] Furthermore, it also includes a second conveying mechanism and a liquid collection box;

[0015] The second conveying mechanism is used to convey the collection box to the underside of the injection head and cover the opening, and to remove the collection box from the opening so that the injection head can fall through the opening and extend into the sample chamber.

[0016] Before sample testing, waste liquid in the pipeline and injection head needs to be drained. After testing, the injection pump, pipeline and injection head need to be cleaned with cleaning fluid. The collection box can be used to collect waste liquid and cleaning fluid.

[0017] Furthermore, trace uranium analysis requires a closed and dark environment, so the sample chamber needs to be in a darkroom state during the detection. Therefore, after the fluorescent enhancer or uranium-based solution is injected, the injection head needs to be withdrawn and the opening sealed to create a darkroom environment.

[0018] Furthermore, it also includes a waste liquid container. The collection box is provided with a drain port, which is connected to the waste liquid container through a pipeline. The accumulated liquid in the collection box can flow into the waste liquid container through the drain port and the pipeline.

[0019] Furthermore, a door is provided on one side of the sample chamber, and a quartz cuvette containing the sample can be placed inside the door after it is opened.

[0020] Furthermore, it also includes a carrying platform and a third conveying mechanism.

[0021] The support platform is used to place quartz cuvettes;

[0022] The third conveying mechanism is used to move the carrying platform out of or back into the sample chamber, thereby facilitating the bringing of quartz cuvettes containing samples into or out of the sample chamber.

[0023] Preferably, the door is positioned on the third conveying mechanism and on the outside of the carrying platform. This allows for automatic opening and closing of the door.

[0024] Furthermore, a magnetic stirrer is provided at the bottom of the sample chamber for stirring the sample in the quartz cuvette inside the sample chamber.

[0025] In use, the stir bar of the magnetic stirrer is placed inside the quartz cuvette. The main unit of the magnetic stirrer rotates, and the magnetic force drives the stir bar to rotate inside the quartz cuvette, thereby stirring the sample.

[0026] Furthermore, a light source (currently, the conventional detection light source is an ultraviolet light source) is provided on one side of the sample chamber; and a detector for detecting fluorescence intensity is also included.

[0027] Preferably, the detector is a silicon photodiode and / or a photomultiplier tube.

[0028] The number of detectors can be one or more; if there are multiple detectors, they can be set on different sides of the sample chamber; or, the detectors can be set outside the sample chamber, and the side wall of the sample chamber has a window that connects to the detector head.

[0029] Furthermore, the main body is also provided with a display screen (preferably a touch screen).

[0030] Furthermore, a printer is embedded in the main body.

[0031] The conveying mechanism preferably adopts an electric telescopic mechanism such as a cylinder, hydraulic cylinder, or slide table.

[0032] Furthermore, it also includes a precision control mechanism for forcing the reagent tail liquid from the injection head to drip into the quartz cuvette.

[0033] According to relevant national industry standards, the amounts of fluorescence enhancer and standard uranium solution used during testing are very small. For example, the substance to be tested is typically dissolved in distilled water or other aqueous solutions to form approximately 5 ml of the sample; during the testing process, the amount of fluorescence enhancer used each time is approximately 500 μL, and the amount of uranium standard solution used is 50 μL. However, due to surface tension, approximately 10-50 μL of the tail liquid remains on the injection head, significantly impacting the accuracy of the test results. This application utilizes a precision control mechanism to force all the tail liquid into the quartz cuvette, thereby effectively ensuring the accuracy of the test results.

[0034] Furthermore, the precision control mechanism includes: an elastic element, an electromagnet, and a connecting block made of a magnetic adsorption material;

[0035] One end of the elastic element is fixed, and the other end is movable; the connecting block and the injection head are disposed on the other end of the elastic element.

[0036] The connecting block is positioned opposite one of the magnetic poles of the electromagnet. When the electromagnet is energized, the magnetic force overcomes the elastic force of the elastic element, forcing the connecting block and the injection head to move until the connecting block abuts against the magnetic pole. When the electromagnet is de-energized, the magnetic force disappears, and the connecting block and the injection head quickly reset under the elastic restoring force of the elastic element, thereby throwing the tail liquid on the injection head into the quartz cuvette below.

[0037] Furthermore, it also includes a limiting block, which is set on the moving path of the connecting block to prevent the connecting block from continuing to move under the action of the elastic restoring force of the elastic element.

[0038] The function of the limiting block is to brake the connecting block and the injection head during rapid movement, so that the tail liquid on the injection head is thrown out by its own inertia and falls into the quartz cuvette.

[0039] The arrangement of the elastic element, electromagnet, connecting block and injection head must meet the following condition: after the tail liquid is thrown out, it moves from top to bottom and falls exactly into the sample solution in the quartz cuvette.

[0040] Furthermore, a buffer pad made of elastic material is provided on the magnetic pole or the connecting block; when the connecting block abuts against the magnetic pole, the buffer pad is clamped between the magnetic pole and the connecting block.

[0041] When the electromagnet is energized, the connecting block and the injection head move rapidly. The buffer pad can prevent direct collision between the connecting block and the magnetic pole, protecting both of them. More importantly, it can buffer and decelerate, preventing the liquid on the injection head from being thrown out. If the liquid is thrown out, it will move from bottom to top and will mostly be thrown outside the quartz cuvette.

[0042] Preferably, the elastic element is an L-shaped elastic rod or elastic sheet.

[0043] Furthermore, the precision control mechanism includes: a spring element, a cam, and a motor; one end of the spring element is fixed, and the other end is movably disposed;

[0044] The injection head is disposed on the other end of the elastic element;

[0045] The annular working surface of the cam has a 360° involute cross-section;

[0046] The elastic element abuts against the working surface of the cam under the action of its own elastic force;

[0047] The motor is used to drive the cam to rotate; as the cam rotates, the radial distance between the elastic element and the center of the cam changes continuously; the elastic element falls from the highest point of the involute back to the lowest point of the involute, and the tail liquid on the injection head is thrown out by its own inertia and falls into the quartz cuvette.

[0048] The motor is preferably a stepper motor; the elastic element is preferably a plate or rod made of elastic material.

[0049] Furthermore, the precision control mechanism includes an air source, an air jet head, and a control valve body; the air jet head is connected to the air source through an air supply pipeline, and the control valve body is installed on the air supply pipeline to control the connection or disconnection between the air jet head and the air source;

[0050] The jet head is positioned in the sample chamber, and when the injection head extends into the sample chamber, the jet head is positioned diagonally above the injection head; the gas blown out from the jet head blows the tail liquid of the test reagent off the edge of the injection head and drips it into the quartz cuvette below.

[0051] Furthermore, the injection pump is a peristaltic pump, which includes a housing with a pump chamber, a rotor rotatably mounted on the housing, and a servo motor coaxially and fixedly connected to the rotor; at least two working wheels are evenly arrayed around the periphery of the rotor.

[0052] Furthermore, it also includes a position sensor for monitoring the position of the work wheel.

[0053] Peristaltic pumps rely on the impeller to compress a flexible pump tube, "squeezing" liquid out of the tube as the rotor rotates. The output volume can be controlled by adjusting the rotation stroke. This working principle also results in intermittent output. This is an inherent characteristic of peristaltic pumps; the same rotation angle will produce different delivery volumes, leading to errors in delivery rate.

[0054] Because the amount of reagent used in trace uranium analysis is small, errors in the delivery volume of the peristaltic pump can easily lead to significant sample detection errors. By incorporating a position sensor, the peristaltic pump's empty stroke can be avoided, and through active compensation by the controller, the delivery volume error of the peristaltic pump can be minimized, ensuring precision.

[0055] Preferably, the position sensor is a Hall sensor or a metal sensor, and the rotor is provided with a sensing block adapted to the position sensor.

[0056] The sensing blocks are set according to the different position sensors, such as magnets adapted to Hall sensors and ferromagnets adapted to metal sensors.

[0057] Furthermore, the sensing block is rotatably mounted on the housing, and the sensing block and the rotor are fixedly positioned relative to each other, with their rotation centers being the same. The sensing block and the rotor rotate synchronously, thereby reflecting the position of the working wheel and compensating for the conveying volume.

[0058] Preferably, the induction block is fixedly mounted on the pivot shaft of the rotor via an intermediate connector.

[0059] More preferably, the sensing block is disposed outside the housing.

[0060] By adopting the above technical solution, the present invention has the following beneficial effects:

[0061] The present invention provides a trace uranium analyzer with a high degree of automation, which can ensure analytical precision and reduce direct contact between staff and samples, thus making it safer and more reliable. Attached Figure Description

[0062] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0063] Figure 1 A perspective view of the trace uranium analyzer provided in Embodiment 1 of the present invention;

[0064] Figure 2 for Figure 1 The diagram shows the internal structure of a trace uranium analyzer after the casing has been removed.

[0065] Figure 3 This is a schematic diagram of the structure of the three conveying mechanisms in Example 1;

[0066] Figure 4 This is a schematic diagram of the precision control mechanism in Embodiment 2 of the present invention;

[0067] Figure 5 This is a schematic diagram of the precision control mechanism in Embodiment 3 of the present invention;

[0068] Figure 6 This is a schematic diagram of the precision control mechanism in Embodiment 4 of the present invention;

[0069] Figure 7 This is a schematic diagram illustrating the working principle of the peristaltic pump in Embodiment 5 of the present invention. Detailed Implementation

[0070] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0071] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0072] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0073] The present invention will be further explained below with reference to specific embodiments.

[0074] Example 1

[0075] like Figure 1-3 As shown, this embodiment provides a trace uranium analyzer, including: a main body 10, an ultraviolet light source 20, a detector 21 (or detection device), and a reagent injection system 30; the main body 10 is provided with a sample chamber 14; the reagent injection system 30 includes a pump 31, a reagent container 32, and an injection head 33; the input end of the pump 31 is connected to the reagent container 32 through an input pipeline, and the output end of the pump 31 is connected to the injection head 33 through an output pipeline, for dripping reagent into a quartz cuvette 1 in the sample chamber 14.

[0076] The detection reagent injection system 30 includes a fluorescence enhancer injection system 30a and a standard uranium liquid injection system 30b. The fluorescence enhancer injection system 30a includes a first injection head 33a, a first injection pump 31a, and a first container 32a connected in sequence through pipelines. The standard uranium liquid injection system 30b includes a second injection head 33b, a second injection pump 31b, and a second container 32b connected in sequence through pipelines.

[0077] This embodiment preferably also includes a first conveying mechanism 41 for delivering or carrying out the two injection heads 33 from the outside into or out of the sample chamber 14. The two injection heads 33 are disposed on the moving end of the first conveying mechanism 41.

[0078] An opening 14a is provided above the sample chamber 14 for the injection head 33 to extend and retract; the first conveying mechanism 41 is a lifting mechanism, and the injection head 33 is located on the telescopic end of the lifting mechanism.

[0079] Furthermore, it also includes a second conveying mechanism 42 and a collection box 44; the second conveying mechanism 42 is used to convey the collection box 44 to the underside of the injection head 33 and cover the opening 14a, and to remove the collection box 44 from the opening 14a so that the injection head 33 can fall through the opening 14a and extend into the sample chamber 14.

[0080] Before sample testing, the waste liquid in the pipeline and the injection head 33 needs to be drained. After testing, the injection pump 31, pipeline and injection head 33 need to be cleaned with cleaning fluid. The collection box 44 can be used to collect waste liquid and cleaning fluid.

[0081] The main body 10 has a waste liquid container 13 below the liquid collection box 44. The liquid collection box 44 is provided with a drain port, which is connected to the waste liquid container 13 through a pipeline. The accumulated liquid in the liquid collection box 44 can flow into the waste liquid container 13 through the drain port and the pipeline.

[0082] Furthermore, trace uranium analysis requires a sealed and dark environment, so the sample chamber 14 needs to be in a darkroom state during the detection. Therefore, after the fluorescent enhancer or quasi-uranium liquid is injected, the injection head 33 needs to be withdrawn and the opening 14a needs to be closed to create a darkroom environment.

[0083] A door 14b is provided on one side of the sample chamber 14. After the door 14b is opened, a quartz cuvette 1 containing the sample can be placed inside.

[0084] Based on the above-described embodiments, the system may preferably further include a support platform 43a and a third conveying mechanism 43. The support platform 43a is used to place the quartz cuvette 1, and the third conveying mechanism 43 is used to move the support platform 43a out of or back into the sample chamber 14. This facilitates the movement of the quartz cuvette 1 containing the sample into or out of the sample chamber 14.

[0085] Preferably, the door body 14b is disposed on the third conveying mechanism 43 and on the outside of the carrying platform 43a. The door body 14b is fixedly connected to the carrying platform 43a, thereby enabling the automatic opening and closing of the door body 14b.

[0086] Furthermore, a magnetic stirrer 45 is provided at the bottom of the sample chamber 14 for stirring the sample in the quartz cuvette 1 within the sample chamber 14. In use, the stir bar of the magnetic stirrer 45 is placed inside the quartz cuvette 1, and the main body of the magnetic stirrer 45 rotates, using magnetic force to drive the stir bar to rotate inside the quartz cuvette 1, thereby achieving stirring of the sample.

[0087] Furthermore, an ultraviolet light source 20 is provided on one side of the sample chamber 14; the detector 21 for detecting fluorescence intensity is a silicon photodiode and / or a photomultiplier tube. The number of detectors 21 can be one or more. If there are multiple detectors, they can be respectively arranged on different sides of the sample chamber 14; alternatively, the detectors 21 can be located outside the sample chamber 14, with windows on the side wall of the sample chamber 14 communicating with the probe head of the detector 21.

[0088] The main body 10 is also equipped with a touch screen display 11. A printer 12 is embedded in the main body 10. The conveying mechanism preferably adopts an electric telescopic mechanism such as a cylinder, hydraulic cylinder, or slide table.

[0089] The present invention provides a trace uranium analyzer with a high degree of automation, which reduces direct contact between personnel and samples, thus making it safer and more reliable.

[0090] Example 2

[0091] This embodiment is basically the same as embodiment 1, except that:

[0092] Reference Figure 3 As shown, this embodiment also includes a precision control mechanism 50 for forcing the reagent tail liquid on the injection head 33 to drip into the quartz cuvette 1. The precision control mechanism 50 is disposed on the moving end of the first delivery mechanism 41, and the injection head 33 is disposed on the precision control mechanism 50.

[0093] During testing, the amounts of fluorescence enhancer and standard uranium solution used are very small. For example, the substance to be tested is usually dissolved in distilled water or other aqueous solutions to form approximately 5 ml of the sample. During the testing process, the amount of fluorescence enhancer used each time is approximately 500 μL, and the amount of uranium standard solution used is 50 μL. The amount of tail liquid (one drop) remaining on the injection head 33 is approximately 10-50 μL. Therefore, this tail liquid has a significant impact on the accuracy of the test results. This application effectively ensures the accuracy of the test results by setting up a precision control mechanism 50 to force all the tail liquid into the quartz cuvette 1.

[0094] Reference Figure 4 As shown, the precision control mechanism 50 in this embodiment includes: an elastic element 51, an electromagnet 52, and a connecting block 55 made of magnetic adsorption material; one end of the elastic element 51 is fixed, and the other end is movably disposed; the connecting block 55 and the injection head 33 are disposed on the other end of the elastic element 51; specifically, the injection head 33 is disposed on the connecting block 55 through a mounting base 33c.

[0095] The connecting block 55 is positioned opposite to one of the magnetic poles 52a of the electromagnet 52. When the electromagnet 52 is energized, it uses magnetic force to overcome the elastic force of the elastic element 51, forcing the connecting block 55 and the injection head 33 to move until the connecting block 55 abuts against the magnetic pole 52a. When the electromagnet 52 is de-energized, the magnetic force disappears, and the connecting block 55 and the injection head 33 quickly reset under the action of the elastic restoring force of the elastic element 51, thereby throwing the tail liquid on the injection head 33 into the quartz cuvette 1 below.

[0096] Furthermore, it also includes a limiting block 55, which is disposed on the moving path of the connecting block 55 to prevent the connecting block 55 from continuing to move under the elastic restoring force of the elastic member 51. The function of the limiting block 55 is to brake the rapidly moving connecting block 55 and the injection head, so that the tail liquid on the injection head is thrown out by its own inertia and falls into the quartz cuvette 1.

[0097] The arrangement of the elastic element 51, electromagnet 52, connecting block 55 and injection head 33 must meet the following condition: after the tail liquid is thrown out, it moves from top to bottom and falls exactly into the sample solution in the quartz cuvette 1.

[0098] More preferably, a buffer pad 54 made of elastic material is provided on the magnetic pole 52a or the connecting block 55; when the connecting block 55 abuts against the magnetic pole 52a, the buffer pad 54 is clamped between the magnetic pole 52a and the connecting block 55.

[0099] When the electromagnet 52 is energized, the connecting block 55 and the injection head move rapidly. The buffer pad 54 prevents direct collision between the connecting block 55 and the magnetic pole 52a, protecting both. More importantly, it buffers and slows down the flow, preventing the liquid on the injection head from being flung out. If the liquid is flung out, it will move upwards and mostly land outside the quartz cuvette 1. Preferably, the elastic element 51 is an L-shaped elastic rod or elastic sheet.

[0100] The precision control mechanism 50 in this embodiment ensures the accuracy of the reagent injection volume, thereby ensuring the accuracy of the test results.

[0101] Example 3

[0102] This embodiment is basically the same as embodiment 1, except that:

[0103] Reference Figure 5As shown, the precision control mechanism 50 in this embodiment includes: a spring element 56, a cam 57, and a motor (not shown); one end of the spring element 56 is fixed, and the other end (free end) is movably disposed; the injection head 33 is disposed on the other end of the spring element 56 through a mounting base 33c; a backing plate 56a is disposed on the free end of the spring element 56; the backing plate 56a abuts against the working surface of the cam 57 under the action of the elastic force of the spring element 56.

[0104] The annular working surface of the cam 57 has a 360° involute cross-section; the motor drives the cam 57 to rotate; during the rotation of the cam 57, the radial distance between the free end of the elastic element 56 and the support plate 56a and the center of the cam 57 continuously changes; the free end of the elastic element 56 and the support plate 56a fall from the highest point of the involute back to the lowest point of the involute, and the tail liquid on the injection head 33 is thrown out by its own inertia and falls into the quartz cuvette 1. The motor is preferably a stepper motor; the elastic element 56 is preferably a U-shaped plate or rod made of elastic material.

[0105] Example 4

[0106] This embodiment is basically the same as embodiment 1, except that:

[0107] Reference Figure 6 As shown, the precision control mechanism 50 in this embodiment includes a gas source (not shown, such as an air pump or gas storage tank), a jet nozzle 58, and a control valve body. The jet nozzle 58 is connected to the gas source via a gas supply pipeline, and the control valve body is located on the gas supply pipeline to control the connection or closure of the jet nozzle 58 and the gas source. The jet nozzle 58 is located inside the sample chamber 14, and when the injection head 33 extends into the sample chamber 14, the jet nozzle 58 is positioned diagonally above the injection head 33. The gas blown out from the jet nozzle 58 blows the reagent tail liquid at the edge of the injection head 33 and drips it into the quartz cuvette 1 below. This embodiment has a simpler structure and is easier to promote.

[0108] Example 5

[0109] This embodiment is basically the same as embodiment 1, except that:

[0110] Reference Figure 7 As shown, the injection pump 31 in this embodiment is a peristaltic pump 60. The peristaltic pump 60 includes a housing 61 with a pump chamber, a rotor 62 rotatably mounted on the housing 61, and a servo motor coaxially fixedly connected to the rotor 62; at least two working wheels 63 are evenly arrayed around the periphery of the rotor 62.

[0111] Preferably, it also includes a position sensor for monitoring the position of the work wheel 63.

[0112] Peristaltic pumps rely on a rotating impeller to compress a flexible pump tube, "squeezing" liquid out of the tube as it rotates. The output volume can be controlled by adjusting the rotation stroke. This working principle results in intermittent output, an inherent characteristic of peristaltic pumps. The same rotation angle will produce different delivery volumes, leading to errors in delivery rate.

[0113] Because the amount of reagent used in trace uranium analysis is small, errors in the delivery volume of the peristaltic pump 60 can easily lead to significant sample detection errors. By setting up a position sensor 70, the empty stroke of the peristaltic pump 60 can be avoided. Through active compensation by the controller, the delivery volume error of the peristaltic pump 60 can be minimized, ensuring precision.

[0114] Preferably, the position sensor 70 is a Hall sensor or a metal sensor, and the rotor 62 is provided with a sensing block 71 adapted to the Hall position sensor 70.

[0115] The sensing block 71 is set according to the different position sensors 70, such as a magnet adapted to a Hall sensor, and a ferromagnetic material adapted to a metal sensor.

[0116] The sensing block 71 is rotatably mounted on the housing 61. The sensing block 71 and the rotor 62 are fixedly mounted relative to each other, and the rotation centers of the sensing block 71 and the rotor 62 are the same. That is, the sensing block 71 rotates synchronously with the rotor 62, thereby reflecting the position of the working wheel 63 and compensating for the conveying amount.

[0117] More preferably, the sensing block 71 is fixedly mounted on the pivot shaft of the rotor 62 via an intermediate connecting member (such as a connecting rod or a connecting disc). More preferably, the sensing block 71 is disposed outside the housing 61, thereby facilitating installation and testing.

[0118] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A trace uranium analyzer, characterized in that, The application relates to a device for detecting a target substance in a sample, comprising a main body, an ultraviolet light source, a detector and a reagent injection system. The main body is provided with a sample chamber. The reagent injection system comprises a liquid injection pump, a reagent container and a liquid injection head. The input end of the liquid injection pump is connected with the reagent container through an input pipeline, and the output end of the liquid injection pump is connected with the liquid injection head through an output pipeline, so as to drop the reagent into a quartz cuvette in the sample chamber. The reagent injection system further comprises a precision control mechanism for forcing the tail liquid of the reagent on the liquid injection head to drop into the quartz cuvette. The precision control mechanism comprises an elastic member, an electromagnet and a connecting block made of magnetic adsorption material. One end of the elastic member is fixed, and the other end is movably arranged. The connecting block and the liquid injection head are arranged on the other end of the elastic member. The connecting block is arranged opposite to one magnetic pole of the electromagnet. When the electromagnet is electrified, the magnetic force overcomes the elastic force of the elastic member to force the connecting block and the liquid injection head to move until the connecting block abuts against the magnetic pole. When the electromagnet is de-energized, the magnetic force disappears, and the connecting block and the liquid injection head are quickly reset under the action of the elastic restoring force of the elastic member, so that the tail liquid on the liquid injection head is thrown into the quartz cuvette below. The reagent injection system further comprises a limiting block arranged on the moving path of the connecting block, which is used for preventing the connecting block from continuously moving under the action of the elastic restoring force of the elastic member.

2. The micro-uranium analyzer according to claim 1, characterized by The magnetic pole or the connecting block is provided with a buffer pad made of elastic material. When the connecting block abuts against the magnetic pole, the buffer pad is clamped between the magnetic pole and the connecting block. The reagent injection system comprises a fluorescence enhancer injection system and a standard uranium liquid injection system.

3. The micro-uranium analyzer according to claim 1, wherein The fluorescence enhancer injection system comprises a first liquid injection head, a first liquid injection pump and a first container connected in sequence through pipelines.

4. The micro-uranium analyzer according to claim 3, characterized by The standard uranium liquid injection system comprises a second liquid injection head, a second liquid injection pump and a second container connected in sequence through pipelines.

5. The micro-uranium analyzer according to claim 4, wherein The reagent injection system further comprises a first conveying mechanism for extending the liquid injection head into the sample chamber from outside. The sample chamber is provided with an opening above the sample chamber for the extension and withdrawal of the liquid injection head.

6. The micro-uranium analyzer according to claim 5, wherein The first conveying mechanism is a lifting mechanism, and the liquid injection head is arranged on the telescopic end of the lifting mechanism.

7. The micro-uranium analyzer of claim 1, wherein, The reagent injection system further comprises a second conveying mechanism and a liquid collecting box.

8. The micro-uranium analyzer according to claim 7, characterized in that, The second conveying mechanism is used for conveying the liquid collecting box to below the liquid injection head and covering the opening, and moving the liquid collecting box away from the opening so that the liquid injection head falls into the sample chamber through the opening. The reagent injection system further comprises a waste liquid container, and the liquid collecting box is provided with a liquid discharge port connected with the waste liquid container through a pipeline. The sample chamber is provided with a door body on one side, and the quartz cuvette containing the sample can be placed into the door body after the door body is opened.

9. The micro-uranium analyzer according to claim 8, wherein The reagent injection system further comprises a bearing platform and a third conveying mechanism.

10. The micro-uranium analyzer of claim 1, wherein, The bearing platform is used for placing the quartz cuvette.

11. The micro-uranium analyzer of claim 1, wherein, The third conveying mechanism is used for moving the bearing platform out of or back into the sample chamber.

12. The micro-uranium analyzer of claim 1, wherein, The door body is arranged on the third conveying mechanism and the outer side of the bearing platform. The bottom of the sample chamber is provided with a magnetic stirrer for stirring the sample in the quartz cuvette in the sample chamber. The detector is a silicon photodiode and / or a photomultiplier tube. The elastic member is an L-shaped elastic rod or an elastic sheet.

13. The micro-uranium analyzer of claim 1, wherein, The liquid injection pump is a peristaltic pump, which comprises a shell provided with a pump chamber, a rotor rotatably arranged on the shell, and a servo motor coaxially and fixedly connected to the rotor; and at least two working wheels are uniformly arranged on the periphery of the rotor.

14. The micro-uranium analyzer of claim 13, wherein, The position sensor is a Hall sensor or a metal sensor, and an induction block adapted to the position sensor is arranged on the rotor.

15. The micro-uranium analyzer of claim 14, wherein, The induction block is rotatably arranged on the shell, and the induction block and the rotor are relatively fixedly arranged and have the same rotation center.

16. The micro-uranium analyzer of claim 15, wherein, The induction block is fixedly arranged on the pivot shaft of the rotor through an intermediate connecting piece.

17. The micro-uranium analyzer of claim 15, wherein, The induction block is arranged outside the shell.

18. The micro-uranium analyzer according to any one of claims 15 to 17, wherein, ​

Images