A stable isotope mass spectrometer ion source

Abstract

The present invention belongs to the technical field of mass spectrometers, and particularly relates to an ion source for a stable isotope mass spectrometer. Its technical solution is as follows: an ion source for a stable isotope mass spectrometer comprises a fixed base, one side of the fixed base is connected to a high-voltage electrode, the other side of the fixed base is provided with a plurality of support columns, the other side of the support columns is connected to a limit seat, an ionization chamber for bombarding a sample, a correction unit for correcting the ion beam, and a slit unit for adjusting the width of the ion beam are sequentially installed between the support columns, an acceleration unit for adjusting the ion beam speed is connected to the limit seat, the fixed base is connected to a cavity, the cavity is sleeved outside the plurality of support columns, the cavity is connected to an injection valve for inputting a sample into the ionization chamber, and the ionization chamber, correction unit, slit unit, and acceleration unit are all connected to the high-voltage electrode via a high-voltage wire. The present invention provides an ion source for a stable isotope mass spectrometer that is convenient for adjusting the width and energy of the ion beam.

Description

Technical Field

[0001] The invention belongs to the technical field of mass spectrometers, and in particular relates to an ion source for a stable isotope mass spectrometer. Background Art

[0002] A mass spectrometer is designed to determine the isotopic composition of chemical elements and their compounds in a gaseous state. The ion source converts gaseous molecules into positive ions and accelerates and focuses them into an ion beam, facilitating subsequent magnetic field analysis of the charged ions. The ion receiver collects the ions analyzed by the electromagnet. The movement of charged ions generates an electric current, which is amplified by an external device. The ratio of the collected ions can be measured, thereby determining the isotope ratios of different mass-to-charge ratios.

[0003] The operating principle of a magnetic mass spectrometer is based on the spatial separation of analyte gas molecules, which are ionized by mass to form an ion beam. The relative abundance of each component and its molecular weight can then be determined. To achieve this, the gas to be analyzed is injected into the mass spectrometer's sample inlet system. After preliminary preparation, it passes through a needle valve into an ion source, which is pumped to a high vacuum. In the ion source, some of the injected gas molecules are ionized when bombarded by an electron beam. The resulting positive or negative ions (depending on the ionization mode) are collected into a narrow beam by the ion source's ion optics and accelerated to energies many times higher than their initial thermal energy. The resulting single ion beam is directed into a transverse uniform magnetic field (analyzer), where it is split into multiple beams, each containing ions with a single m / e value (ion mass / ion charge). By varying the induction of the magnetic field, the ion beam with the desired m / e value can be directed into the collector of the ion receiver. The ions of each ion beam contribute their charge to the ion collector, that is, they generate a current in its circuit. The magnitude of this current serves as a measure of the component's concentration in the sample gas.

[0004] In the prior art, the width and energy of the ion beam generated by the sample are not easy to adjust. Summary of the Invention

[0005] In order to solve the above problems existing in the prior art, an object of the present invention is to provide an ion source for a stable isotope mass spectrometer that is convenient for adjusting the ion beam width and energy.

[0006] The technical solution adopted in the present invention is:

[0007] An ion source for a stable isotope mass spectrometer comprises a fixed base, one side of which is connected to a high-voltage electrode, a plurality of support columns are arranged on the other side of the fixed base, the other side of the support columns is connected to a limiting seat, an ionization chamber for bombarding a sample, a correction unit for correcting an ion beam, and a slit unit for adjusting the width of the ion beam are sequentially installed between the support columns, an acceleration unit for adjusting the speed of the ion beam is connected to the limiting seat, the fixed base is connected to a cavity, the cavity is sleeved outside the plurality of support columns, the cavity is connected to an injection valve for inputting a sample into the ionization chamber, and the ionization chamber, the correction unit, the slit unit, and the acceleration unit are all connected to the high-voltage electrode via a high-voltage wire.

[0008] The gas sample enters the ionization chamber through the injection valve. The electrons emitted from the ionization chamber bombard the gas molecules, ionizing them. The ion beam generated by the ionization chamber is corrected by the correction unit so that it accurately enters the slit unit. The slit unit adjusts the width of the ion beam, thereby adjusting the sensitivity and resolution of the ion beam. The acceleration unit accelerates the ion beam, ultimately obtaining an ion beam of a certain width and energy. High-voltage electrodes provide power to each unit, including the ionization chamber, correction unit, slit unit, and acceleration unit. The ion source of the present invention has a simple structural layout, can accurately correct the ion beam, and can adjust the width and energy of the ion beam.

[0009] As a preferred embodiment of the present invention, a servo spring is connected to the fixed base, the other end of which is connected to a mounting seat. The support column is fixed to the mounting seat, and a retaining structure is provided within the cavity to block the retaining seat. The servo spring pushes the mounting seat, support column, and retaining seat outward, causing the retaining seat to press against the retaining structure within the cavity. When the position of the various components is adjusted using washers, the end face of the retaining seat remains in the same position, allowing the retaining seat to accurately connect with the locating pin in the vacuum line of the analysis system.

[0010] As a preferred embodiment of the present invention, an emitter filament for emitting electrons is provided on one side of the ionization chamber, a receiver filament for receiving electrons is provided on the other side of the ionization chamber, and the injection valve is connected to the ionization chamber through a pipeline.

[0011] As a preferred embodiment of the present invention, a repelling electrode is provided on the lower side of the ionization chamber, and a potential is applied to the repelling electrode to form an electrostatic field to push the ions generated in the ionization chamber to pass through the correction unit.

[0012] As a preferred embodiment of the present invention, permanent magnets are positioned on either side of the ionization chamber. These permanent magnets are connected to a cavity, which is also connected to an adjustment device for adjusting the position of the permanent magnets. The adjustment device can adjust the permanent magnets in three directions: the X-axis, the Y-axis, and the Z-axis, ultimately causing the electrons to move in a spiral motion, thereby increasing the probability of electrons bombarding gas molecules.

[0013] As a preferred embodiment of the present invention, the correction unit includes a correction electrode, an X-direction correction electrode, and a Y-direction correction electrode, which are sequentially arranged. The correction electrode is provided with a correction slit. The X-direction correction electrode is provided with a correction slit in the X-axis direction, and the Y-direction correction electrode is provided with a correction slit in the Y-axis direction. The correction electrode, the X-direction correction electrode, and the Y-direction correction electrode adjust the ion beam in each direction to ensure that the ion beam travels along a predetermined path.

[0014] As a preferred embodiment of the present invention, the slit unit comprises two springs, one end of which is fixed relative to the support column. A linear feed device is connected to the cavity, and the other end of the spring is connected to the output end of the linear feed device. Oppositely arranged slit plates are connected to the two springs. The linear feed device can adjust the degree of compression between the two springs, thereby changing the degree of curvature of the springs. The middle of the spring drives the slit plates to move, adjusting the slit spacing between the two slit plates. The ion beam passes through the slits, thereby adjusting the width of the ion beam to the desired width, thereby accurately adjusting the sensitivity and resolution of the ion beam.

[0015] As a preferred solution of the present invention, a tiny correction electrode is connected inside the slit plate. The tiny positive electrode can perform a tiny correction on the ion beam to ensure that the ion beam enters the acceleration unit smoothly.

[0016] As a preferred solution of the present invention, the acceleration unit includes three groups of accelerating electrodes arranged in sequence. The three groups of accelerating electrodes accelerate the ion beam so that the ion beam entering the analysis system has a certain energy value.

[0017] As a preferred solution of the present invention, a plug-in valve connector and an analysis system connector are provided on the cavity.

[0018] The beneficial effects of the present invention are:

[0019] 1. The ion beam generated by the ionization chamber of the present invention is corrected by a correction unit, allowing it to accurately enter the slit unit. The slit unit adjusts the width of the ion beam, thereby adjusting the sensitivity and resolution of the ion beam. The acceleration unit accelerates the ion beam, ultimately producing an ion beam of a predetermined width and energy. The ion source of the present invention has a simple structural layout, enables accurate correction of the ion beam, and can adjust the width and energy of the ion beam.

[0020] 2. Under the thrust of the servo spring, the limit seat can be pressed against the limit structure of the chamber. When the position of each component is adjusted through the gasket, the end position of the limit seat remains unchanged, so that the limit seat can accurately connect with the positioning pin in the vacuum line of the analysis system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the present invention;

[0022] Figure 2is a cross-sectional view of the present invention;

[0023] Figure 3 It is a cross-sectional view of a part of the structure of the present invention;

[0024] Figure 4 yes Figure 3 Schematic diagram of the structure in the AA direction;

[0025] Figure 5 yes Figure 3 A partial enlarged view of point B in the middle;

[0026] Figure 6 yes Figure 3 A partial enlarged view of point C in the middle;

[0027] Figure 7 Front view of the ionization chamber;

[0028] Figure 8 This is a top view of the ionization chamber.

[0029] In the figure: 1-fixed base; 2-high voltage electrode; 3-support column; 4-limit seat; 5-ionization chamber; 6-correction unit; 7-slit unit; 8-acceleration unit; 9-cavity; 11-servo spring; 12-mounting seat; 51-emitter filament; 52-receiving electrode filament; 53-repelling electrode; 61-correction electrode; 62-X-direction correction electrode; 63-Y-direction correction electrode; 71-spring; 72-slit plate; 73-micro correction electrode; 81-acceleration electrode; 91-injection valve; 92-permanent magnet; 93-adjustment device; 94-linear feed device; 95-plug valve connector; 96-analysis system connector. DETAILED DESCRIPTION

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of 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. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0031] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. It should be noted that the embodiments of the present invention and the features therein may be combined with each other unless there is a conflict.

[0032] like Figures 1 to 3As shown, the ion source of the stable isotope mass spectrometer of this embodiment includes a fixed base 1, one side of which is connected to a high-voltage electrode 2, and the other side of the fixed base 1 is provided with a plurality of support columns 3. The other side of the support columns 3 is connected to a limit seat 4. An ionization chamber 5 for bombarding the sample, a correction unit 6 for correcting the ion beam, and a slit unit 7 for adjusting the ion beam width are sequentially installed between the support columns 3. The limit seat 4 is connected to an acceleration unit 8 for adjusting the ion beam speed. The fixed base 1 is connected to a cavity 9, which is sleeved outside the plurality of support columns 3. The cavity 9 is connected to an injection valve 91 for inputting the sample into the ionization chamber 5. The ionization chamber 5, the correction unit 6, the slit unit 7, and the acceleration unit 8 are all connected to the high-voltage electrode 2 via high-voltage wires. The cavity 9 is provided with a gate valve connector 95 and an analysis system connector 96.

[0033] The gas sample enters the ionization chamber 5 from the injection valve 91, and the electrons emitted from the ionization chamber 5 bombard the gas molecules, causing the gas molecules to be ionized. The ion beam generated by the ionization chamber 5 is corrected by the correction unit 6 so that it accurately enters the slit unit 7. The slit unit 7 adjusts the width of the ion beam, thereby adjusting the sensitivity and resolution of the mass spectrometry system. The acceleration unit 8 accelerates the ion beam and ultimately obtains an ion beam of a determined width and energy. The high-voltage electrode 2 provides power to each unit, such as the ionization chamber 5, the correction unit 6, the slit unit 7 and the acceleration unit 8. The ion source structure of the present invention is simple in layout, can accurately correct the ion beam, and can adjust the width and energy of the ion beam.

[0034] Furthermore, a servo spring 11 is connected to the fixed base 1, and the other end of the servo spring 11 is connected to a mounting seat 12, the support column 3 is fixed to the mounting seat 12, and a limiting structure that blocks the limiting seat 4 is provided in the cavity 9. The servo spring 11 pushes the mounting seat 12, the support column 3 and the limiting seat 4 outward, so that the limiting seat 4 can be pressed against the limiting structure of the cavity 9. The required distance between the lenses is ensured by a ceramic gasket that is operated remotely. When the positions of the components are adjusted by the gasket, the end face position of the limiting seat 4 remains unchanged, so that the limiting seat 4 can be accurately connected to the locating pin in the vacuum pipeline of the analysis system. The position of the limiting seat 4 does not depend on the thickness of the gasket between the ion source and the vacuum pipeline, nor on the tightening force of the bolts of the sealed ion source flange.

[0035] Specifically, if Figure 7 and Figure 8As shown, an emitter filament 51 for emitting electrons is provided on one side of the ionization chamber 5, and a receiver filament 52 for receiving electrons is provided on the other side of the ionization chamber 5. An injection valve 91 is connected to the ionization chamber 5 via a pipeline. A repelling electrode 53 is provided on the lower side of the ionization chamber 5, and a potential is applied to the repelling electrode 53. The repelling electrode 53 generates an electrostatic field, which propels the ions generated in the ionization chamber 5 through the calibration unit 6. The emitter filament 51 and the receiver filament 52 can be tungsten filaments.

[0036] To regulate the spiral motion of the electrons, permanent magnets 92 are installed on both sides of the ionization chamber 5. These permanent magnets are connected to the cavity 9, which is also connected to an adjustment device 93 for adjusting the position of the permanent magnets. The adjustment device 93 can adjust the permanent magnets 92 along the X-axis, Y-axis, and Z-axis, ultimately causing the electrons to spiral and increase the probability of electron bombardment of gas molecules.

[0037] like Figure 6 As shown, the correction unit 6 includes a correction electrode 61, an X-direction correction electrode 62, and a Y-direction correction electrode 63, which are arranged in sequence. The correction electrode 61 is provided with a correction slit, the X-direction correction electrode 62 is provided with a correction slit in the X-axis direction, and the Y-direction correction electrode 63 is provided with a correction slit in the Y-axis direction. The correction electrode 61, the X-direction correction electrode 62, and the Y-direction correction electrode 63 adjust the ion beam in each direction to ensure that the ion beam travels along a predetermined path.

[0038] like Figures 3 to 5 As shown, the slit unit 7 includes two springs 71, one end of which is fixed relative to the support column 3, a linear feed device 94 is connected to the cavity 9, and the other end of the spring 71 is connected to the output end of the linear feed device 94. The two springs 71 are connected to oppositely arranged slit plates 72. The linear feed device 94 can adjust the degree of compression of the two springs 71, thereby changing the degree of bending of the springs 71. The middle part of the spring 71 drives the slit plate 72 to move, and the slit spacing between the two slit plates 72 is adjusted. The ion beam passes through the slit, so that the width of the ion beam is adjusted to the required width, so that the sensitivity and resolution of the ion beam are accurately adjusted. The slit width adjustment range is: 0.05~0.5mm. A tiny correction electrode 73 is connected to the slit plate 72. The tiny positive electrode can make a tiny correction to the ion beam to ensure that the ion beam enters the acceleration unit 8 smoothly.

[0039] The acceleration unit 8 includes three groups of acceleration electrodes 81 arranged in sequence. The three groups of acceleration electrodes 81 accelerate the ion beam so that the ion beam entering the analysis system has a certain energy value.

[0040] The present invention is not limited to the above-mentioned optional implementation modes. Anyone can derive other forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, any technical solution that falls within the scope defined by the claims of the present invention falls within the scope of protection of the present invention.

Claims

1. A stable isotope mass spectrometer ion source, characterized in that: The invention comprises a fixed base (1), one side of the fixed base (1) is connected to a high-voltage electrode (2), the other side of the fixed base (1) is provided with a plurality of support columns (3), the other side of the support columns (3) is connected to a limiting seat (4), an ionization chamber (5) for bombarding a sample, a correction unit (6) for correcting an ion beam, and a slit unit (7) for adjusting the width of the ion beam are sequentially installed between the support columns (3), an acceleration unit (8) for adjusting the speed of the ion beam is connected to the limiting seat (4), the fixed base (1) is connected to a cavity (9), the cavity (9) is sleeved outside the plurality of support columns (3), the cavity (9) is connected to an injection valve (91) for inputting a sample into the ionization chamber (5), and the ionization chamber (5), the correction unit (6), the slit unit (7) and the acceleration unit (8) are all connected to the high-voltage electrode (2) through a high-voltage wire; The correction unit (6) comprises a correction electrode (61), an X-direction correction electrode (62), and a Y-direction correction electrode (63) which are arranged in sequence, the correction electrode (61) being provided with a correction slit, the X-direction correction electrode (62) being provided with a correction slit in the X-axis direction, and the Y-direction correction electrode (63) being provided with a correction slit in the Y-axis direction; The slit unit (7) comprises two spring pieces (71), one end of the spring piece (71) is fixed relative to the support column (3), a linear feed device (94) is connected to the cavity (9), the other end of the spring piece (71) is connected to the output end of the linear feed device (94), and the two spring pieces (71) are connected to oppositely arranged slit plates (72).

2. The ion source for a stable isotope mass spectrometer according to claim 1, characterized in that: A servo spring (11) is connected to the fixed base (1), the other end of the servo spring (11) is connected to the mounting seat (12), the support column (3) is fixed to the mounting seat (12), and a limiting structure for blocking the limiting seat (4) is provided in the cavity (9).

3. The ion source for a stable isotope mass spectrometer according to claim 1, characterized in that: An emitter filament (51) for emitting electrons is provided on one side of the ionization chamber (5), and a receiver filament (52) for receiving electrons is provided on the other side of the ionization chamber (5). The injection valve (91) is connected to the ionization chamber (5) through a pipeline.

4. The ion source for a stable isotope mass spectrometer according to claim 3, characterized in that: A repelling electrode (53) is provided on the lower side of the ionization chamber (5), and a potential is applied to the repelling electrode (53).

5. The ion source for a stable isotope mass spectrometer according to claim 1, characterized in that: Permanent magnets (92) are provided on both sides of the ionization chamber (5), and the permanent magnets are connected to the cavity (9). The cavity (9) is also connected to an adjustment device (93) for adjusting the position of the permanent magnets.

6. The ion source for a stable isotope mass spectrometer according to claim 1, characterized in that: A micro correction electrode (73) is connected inside the slit plate (72).

7. The ion source for a stable isotope mass spectrometer according to claim 1, characterized in that: The acceleration unit (8) comprises three groups of acceleration electrodes (81) arranged in sequence.

8. The ion source for a stable isotope mass spectrometer according to any one of claims 1 to 7, characterized in that: The cavity (9) is provided with a plug valve connector (95) and an analysis system connector (96).

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