A sampling device

Abstract

The present application discloses a sampling device, comprising: a body; a sample tray arranged on the body; a moving part arranged on the body and capable of reciprocating on the body, and a transfer chamber is provided on the moving part, the transfer chamber can receive the sample sent by the sample tray, and can transfer the sample to the analyzer as the moving part moves; a processing system arranged on the body and capable of performing helium purge and vacuuming on the sample in the transfer chamber. The above-mentioned sampling device can realize automatic sampling of the sample through the relay transportation of the sample by the sample tray and the moving part, and in the process of the moving part transporting the sample, the helium purge and vacuuming of the sample can be realized through the processing system, so that the adsorbents (air and water, etc.) on the surface of the sample are stripped off by the helium purge, and the stripped adsorbents (air and water, etc.) on the surface of the sample are removed by vacuuming, thereby reducing the background of the analysis to the maximum extent, and significantly improving the accuracy and sensitivity of elemental analysis and isotope analysis.

Description

Technical Field

[0001] The invention relates to the technical field of analytical instruments, and in particular to a sample injection device. Background Art

[0002] In the pretreatment of elemental analysis and isotope analysis, the sampling device has a great influence on the precision and accuracy of the analysis. Therefore, a well-designed and efficient sampling device is crucial in analyzing the element content and isotope composition of the sample.

[0003] In the work of using an elemental analyzer to analyze samples, the samples are generally dropped directly from the sample tray into the elemental analyzer. Although the samples are pre-treated by high-temperature baking before analysis, it is difficult to completely remove the air adsorbed on the surface of the samples and a small amount of water vapor in the atmosphere, especially powder samples. The impurities (i.e., air and moisture) adsorbed on the surface of these samples will directly affect the background of sample analysis, and for some samples with low element content, it will seriously affect the accuracy and sensitivity of the analysis. Summary of the invention

[0004] In view of this, the present invention provides a sample injection device, which works in conjunction with an analyzer to significantly improve the accuracy and sensitivity of analyzing samples.

[0005] In order to achieve the above object, the present invention provides the following technical solution: a sample injection device, comprising:

[0006] Body;

[0007] A sample tray disposed on the body;

[0008] A moving part is arranged on the body and can reciprocate on the body, and a transfer cavity is opened on the moving part, the transfer cavity can receive the sample sent by the sample tray, and can transfer the sample to the analyzer as the moving part moves;

[0009] A processing system is arranged on the machine body and is capable of performing helium purging and vacuuming on the sample in the transfer chamber.

[0010] Preferably, in the above-mentioned sample injection device, the moving member is a moving rod disposed in the inner cavity of the body and axially reciprocates in the inner cavity.

[0011] Preferably, in the above-mentioned sample injection device, a sample outlet hole is provided on the body, the sample outlet hole is located at the bottom of the movable member, and the sample can enter the reaction tube of the analyzer from the transfer chamber through the sample outlet hole.

[0012] Preferably, in the above-mentioned injection device, the transfer chamber is opened along the radial direction of the movable part and passes through the movable part, so that the sample on the sample disk can fall into the transfer chamber when the transfer chamber moves to the injection position, and the sample in the transfer chamber can fall into the sample outlet hole when the transfer chamber moves to the sample outlet position.

[0013] Preferably, in the above-mentioned sampling device, the processing system includes a helium pipeline, a vacuum pipeline and a solenoid valve. When the transfer chamber moves to the processing position, the helium pipeline and the vacuum pipeline are alternately connected to the transfer chamber, and the solenoid valve is connected to the vacuum pipeline and the helium pipeline through a vacuum interface and a helium interface respectively to control the opening and closing of the vacuum pipeline and the helium pipeline.

[0014] Preferably, in the above-mentioned sample injection device, in the axial direction of the movable member, the processing position is located between the sample injection position and the sample output position.

[0015] Preferably, in the above-mentioned sampling device, a plurality of sealing rings are sleeved on the movable part, all of which are sealingly connected to the circumferential outer wall of the movable part and the inner wall of the inner cavity, and are respectively located on both sides of the transfer cavity, so that the transfer cavity remains airtight when connected to the helium pipeline and the vacuum pipeline.

[0016] Preferably, in the above-mentioned sample injection device, the sample tray is rotatably arranged on the machine body, and a first compressed air inlet is arranged on the machine body, and the compressed air entering from the first compressed air inlet is used to drive the sample tray to rotate.

[0017] Preferably, in the above-mentioned sample injection device, a second compressed air inlet is provided on the body, and the compressed air entering from the second compressed air inlet is used to drive the moving part to move reciprocally.

[0018] Preferably, in the above-mentioned sample injection device, a vacuum gauge is provided in the transfer chamber.

[0019] The present invention discloses the following technical effects:

[0020] The sample injection device provided by the present invention can realize automatic sample injection by relaying the sample through the sample tray and the moving part, and in the process of the moving part transporting the sample, the helium purging and vacuuming of the sample can be realized through the processing system, so that the air adsorbed by the sample is removed by the helium purging, and the moisture adsorbed by the sample is removed by the vacuuming, thereby minimizing the background of the analysis and significantly improving the accuracy and sensitivity of element analysis and isotope analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0022] Figure 1 A schematic diagram of the structure of a sample injection device provided in an embodiment of the present invention.

[0023] exist Figure 1 Middle: 1-sample tray, 2-moving part, 3-sample outlet, 4-vacuum interface, 5-helium interface, 6-transfer chamber, 7-solenoid valve, 8-sealing ring, 9-first compressed air inlet, 10-second compressed air inlet, 11-machine body. DETAILED DESCRIPTION

[0024] The present invention provides a sample injection device, which can work in conjunction with an analyzer to significantly improve the accuracy and sensitivity of analyzing samples.

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] like Figure 1 As shown, an embodiment of the present invention provides a sample injection device, which is used to cooperate with an analyzer. The sample injection device mainly includes: a body 11; a sample tray 1 arranged on the body 11, and the sample tray 1 is used to temporarily place weighed samples to be analyzed; a moving part 2 arranged on the body 11 and capable of reciprocating on the body 11, and a transfer chamber 6 is opened on the moving part 2, and the transfer chamber 6 can receive the sample sent by the sample tray 1, and can transfer the sample to the analyzer as the moving part 2 moves, so as to realize the transportation of the sample to the analyzer; a processing system arranged on the body 11, and capable of performing helium purge and vacuuming on the sample located in the transfer chamber 6.

[0027] The above-mentioned sample introduction device can perform helium purge and vacuum on the sample in the transfer chamber 6 through the processing system during the sample transportation process, thereby removing impurities such as air and moisture adsorbed by the sample, so that the accuracy and sensitivity of sample element analysis and isotope analysis can be greatly improved.

[0028] In order to further optimize the technical solution, in the sample injection device provided in this embodiment, Figure 1As shown, the moving member 2 is a moving rod arranged in the inner cavity of the body 11, and axially reciprocates in the inner cavity. Selecting the moving member 2 to be a rod-shaped member and arranging it in the inside of the body 11 can not only simplify the structure of the sample introduction device and reduce its volume, but also can more easily realize the sealing of the transfer chamber 6 through the cooperation of the inner cavity and the moving rod, so this structure is used as the preferred structure of the present embodiment. In addition, under the premise of ensuring normal operation, the moving member 2 can also be arranged on the outside of the body 11.

[0029] like Figure 1 As shown, a sample outlet 3 is provided on the body 11, and the sample outlet 3 is preferably located at the bottom of the moving part 2, and the sample can enter the reaction tube of the analyzer from the transfer chamber 6 through the sample outlet 3. In this embodiment, the structure for the sample to enter the analyzer from the sample injection device is preferably a sample outlet 3 provided on the body 11 and capable of communicating with the transfer chamber 6 (in addition, a delivery pipe specifically used to connect the transfer chamber 6 and the reaction tube of the analyzer can also be provided). This structure can simplify the overall structure of the sample injection device, and the sample outlet 3 is located at the bottom of the moving part 2, and the transfer chamber 6 can also allow the sample to fall directly into the reaction tube under the action of its own weight when the transfer chamber 6 is connected with the sample outlet 3, so that there is no need to provide a special driving component, so as to reduce the manufacturing cost of the sample injection device and improve the working performance.

[0030] like Figure 1 As shown, in this embodiment, the transfer chamber 6 is preferably opened along the radial direction of the moving member 2 and penetrates the moving member 2, so that the sample on the sample disk 1 moves to the injection position (i.e. Figure 1 The sample in the transfer chamber 6 can fall into the transfer chamber 6 when the transfer chamber 6 moves to the sample outlet position (i.e. Figure 1 The transfer chamber 6 is opened along the radial direction of the movable member 2, which is conducive to the cooperation between the movable member 2 and the sample tray 1 located at the top thereof and the sample outlet 3 located at the bottom thereof, that is, in the process of sample transportation, when the transfer chamber 6 is moved to the injection position by the movement of the movable member 2, since the transfer chamber 6 is aligned with the sample tray 1 at this time, the sample on the sample tray 1 can be directly dropped into the transfer chamber 6 from the top entrance of the transfer chamber 6. When the movable member 2 moves the transfer chamber 6 to the sample outlet position by movement, the bottom outlet of the transfer chamber 6 is aligned with and connected to the sample outlet 3, and the sample in the transfer chamber 6 can directly drop into the sample outlet 3 through the bottom outlet, and finally enter the reaction tube of the analyzer.

[0031] In this embodiment, the preferred processing system includes a helium pipeline, a vacuum pipeline and a solenoid valve 7, such as Figure 1As shown, when the transfer chamber 6 moves to the processing position, the helium pipeline and the vacuum pipeline are alternately connected to the transfer chamber 6, and the solenoid valve 7 is connected to the vacuum pipeline and the helium pipeline through the vacuum interface 4 and the helium interface 5 respectively to control the on and off of the vacuum pipeline and the helium pipeline, and the helium pipeline is externally connected to a high-purity helium source, and the vacuum pipeline is externally connected to a vacuum dry pump. When the transfer chamber 6 moves to the sampling position to receive the sample, the moving part 2 will drive the sample in the transfer chamber 6 to move to the sampling position. During this movement, the transfer chamber 6 will first move to the sample processing position (i.e. Figure 1 The position marked with B in the figure) is used to connect the helium pipeline and the vacuum pipeline with the transfer chamber 6 so that the sample in the transfer chamber 6 can be processed. When processing, the helium pipeline is first connected with the transfer chamber 6 through the electromagnetic valve 7, so that the helium purge of the sample is achieved by introducing helium into the transfer chamber 6. After the purge is completed, the helium pipeline is disconnected through the electromagnetic valve 7, and then the electromagnetic valve 7 controls the vacuum pipeline to connect with the transfer chamber 6. Under the vacuum action of the vacuum dry pump, the transfer chamber 6 is evacuated to remove the air in the transfer chamber 6 and the gas adsorbed on the surface of the sample (including air and water vapor). Then the electromagnetic valve 7 is disconnected from the vacuum pipeline. The above-mentioned helium purge and vacuum pumping are performed alternately for 4-6 times, and the vacuum degree in the transfer chamber 6 is detected by a vacuum gauge. When the vacuum degree reaches 10 -2 -10 -3 mbar, it can be considered that the air and water adsorbed on the sample surface have been processed and the processing operation is completed. Then, the sample with impurities removed moves to the sample outlet position and enters the sample outlet hole 3.

[0032] like Figure 1 As shown, in the axial direction of the moving member 2, the processing position is preferably located between the sample injection position and the sample output position. Such an arrangement enables the sample in the transfer chamber 6 to pass through the processing position in the process of approaching the sample output position, thereby avoiding the increase in the moving distance of the moving member 2 due to the processing position being arranged on the same side of the sample injection position and the sample output position, thereby improving the working performance of the sample injection device.

[0033] Furthermore, in this embodiment, the moving member 2 is preferably provided with a plurality of sealing rings 8, such as Figure 1As shown, all the sealing rings 8 are sealingly connected to the circumferential outer wall of the moving part 2 and the inner wall of the inner cavity of the body 11, and are respectively located on both sides of the transfer chamber 6, so that the transfer chamber 6 remains airtight when it is connected to the helium pipeline and the vacuum pipeline. Since the airtightness of the transfer chamber 6 needs to be ensured when the sample in the transfer chamber 6 is processed, a sealing ring 8 is arranged between the circumferential outer wall of the moving part 2 and the inner wall of the inner cavity of the body 11. The sealing of the sealing ring 8 makes the transfer chamber 6 become a closed space when it is not located at the injection position and the sample output position, thereby ensuring the smooth progress of helium purging and vacuuming. In addition, the airtightness of the transfer chamber 6 can also be achieved by other means, such as providing sealing doors that can be opened and closed at the top inlet and the bottom outlet of the transfer chamber 6. In addition, in the present embodiment, it is preferred that there are three sealing rings 8, such as Figure 1 shown.

[0034] Specifically, Figure 1 As shown, the sample tray 1 is arranged on the body 11 for rotation, and the body 11 is also provided with the first compressed air inlet 9, and the compressed air entering from the first compressed air inlet 9 is used to drive the sample tray 1 to rotate, and simultaneously, the body 11 is provided with the second compressed air inlet 10, and the compressed air entering from the second compressed air inlet 10 is used to drive the reciprocating movement of the moving member 2. That is, the reciprocating movement of the moving member 2 and the rotation of the sample tray 1 in the present embodiment are all preferably realized by the driving of compressed air. In addition, the motion of the moving member 2 and the sample tray 1 can also be driven by other types of driving modes, for example, driven by parts such as motors, cylinders, hydraulic cylinders.

[0035] In this embodiment, a vacuum gauge is preferably provided in the transfer chamber 6 so that the sample processing can be monitored by the vacuum gauge, thereby minimizing the background of the analysis. In addition, the sample processing can also be obtained by other monitoring methods, such as providing a vacuum gauge, a flow meter, etc. on the vacuum pipeline.

[0036] The following uses the analysis of the carbon content in minerals and the analysis of the water content and isotopic composition in minerals as examples to illustrate the specific working process of the sampling device:

[0037] When analyzing the carbon content in minerals, the sample is first baked. For inorganic samples, the baking temperature can be appropriately increased, generally 150°C-200°C, and the baking time is 24 hours. For organic samples, the baking temperature is generally set to 80°C-120°C, and the baking time is 12 hours. Then the sample is accurately weighed and wrapped in a high-purity tin cup, and the weighed sample is placed in the sample tray 1. The sample tray 1 rotates, and the sample falls into the transfer chamber 6 located at the injection position. The transfer chamber 6 then moves to the processing position. At this time, under the control of the solenoid valve 7, the sample is alternately purged with helium and evacuated. Using a vacuum gauge, when the vacuum degree of the transfer chamber 6 reaches 10 -2mbar, it can be considered that the impurities adsorbed by the sample are basically removed; then the transfer chamber 6 moves to the sample outlet position, and the sample falls into the oxidation-reduction reaction tube in the helium environment for reaction; the tail gas is separated by the GC column, and the carbon content in the mineral can be obtained according to the amount of carbon dioxide.

[0038] When analyzing the water content and H isotope composition in minerals, the sample is first baked. For hydrous minerals, the baking temperature is 100°C-120°C and the baking time is 6 hours. For nominally anhydrous minerals (i.e., the molecular formula does not contain water), the baking temperature is 120°C-150°C and the baking time is 8 hours. Then, the sample is accurately weighed and wrapped in a high-purity silver cup, and the weighed sample is placed in a sample tray 1. The sample tray 1 rotates, and the sample falls into a transfer chamber 6 located at the injection position. Since the water adsorbed on the surface of the sample is difficult to remove, the temperature in the transfer chamber 6 needs to be set to 100°C. Then, the transfer chamber 6 is moved to the processing position. At this time, under the control of the solenoid valve 7, the sample is alternately purged with helium and evacuated. Since the water adsorbed on the surface of the sample is relatively difficult to remove, the time for purging and evacuating the sample with helium needs to be longer. Using a vacuum gauge, when the vacuum degree of the transfer chamber 6 reaches 10 -2 mbar, it can be considered that the impurities adsorbed by the sample are basically removed; then the transfer chamber 6 moves to the sample outlet position, and the sample falls into the carbon reduction furnace under the helium environment; the tail gas is separated by the GC column and then enters the isotope gas mass spectrometer, and the mineral water content and H isotope composition can be calculated based on the peak area of ​​hydrogen.

[0039] In summary, the sample injection device provided in this embodiment has the following advantages compared with the traditional sample injection device:

[0040] (1) Higher analytical accuracy. By purging and vacuuming the sample with helium before injection, the influence of adsorbed impurities on the analysis can be basically eliminated. Compared with the traditional operation method, the analytical accuracy can be improved by an order of magnitude;

[0041] (2) Higher analytical sensitivity. Traditional operation methods are often unable to measure samples with extremely low content due to the influence of adsorbed impurities. The sample injection device provided in this embodiment can successfully achieve zero background, greatly improving the analytical sensitivity.

[0042] In this specification, each part of the structure is described in a progressive manner, and the structure of each part focuses on the differences from the existing structure. The overall and partial structures of the injection device can be obtained by combining the structures of the above multiple parts.

[0043] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A sample injection device, characterized in that: include: Body; A sample tray disposed on the body; A moving part is arranged on the body and can reciprocate on the body, and a transfer cavity is opened on the moving part, the transfer cavity can receive the sample sent by the sample tray, and can transfer the sample to the analyzer as the moving part moves; A processing system disposed on the machine body and capable of performing helium purging and vacuuming on the sample in the transfer chamber; The moving member is a moving rod disposed in the inner cavity of the body and axially reciprocates in the inner cavity. The moving rod is a rod-shaped member and is disposed inside the body. The body is provided with a sample outlet hole, the sample outlet hole is located at the bottom of the moving part, and the sample can enter the reaction tube of the analyzer from the transfer chamber through the sample outlet hole; The transfer chamber is opened along the radial direction of the moving member and penetrates the moving member, so that the sample on the sample disk can fall into the transfer chamber when the transfer chamber moves to the sample injection position, and the sample in the transfer chamber can fall into the sample outlet hole when the transfer chamber moves to the sample outlet position; The processing system includes a helium pipeline, a vacuum pipeline and a solenoid valve. When the transfer chamber moves to the processing position, the helium pipeline and the vacuum pipeline are alternately connected to the transfer chamber. The solenoid valve is respectively connected to the vacuum pipeline and the helium pipeline through a vacuum interface and a helium interface to control the opening and closing of the vacuum pipeline and the helium pipeline. The moving part is sleeved with a plurality of sealing rings, all of which are sealingly connected to the circumferential outer wall of the moving part and the inner wall of the inner cavity, and are respectively located on both sides of the transfer cavity, so that the transfer cavity remains airtight when connected to the helium pipeline and the vacuum pipeline; The processing position is located between the sample injection position and the sample output position.

2. The sample injection device according to claim 1, characterized in that: The sample tray is rotatably arranged on the machine body, and a first compressed air inlet is arranged on the machine body, and the compressed air entering from the first compressed air inlet is used to drive the sample tray to rotate.

3. The sample injection device according to claim 2, characterized in that: The machine body is provided with a second compressed air inlet, and the compressed air entering from the second compressed air inlet is used to drive the moving member to move back and forth.

4. The sample injection device according to claim 3, characterized in that: A vacuum gauge is arranged in the transfer chamber.

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