Mass spectrometer

Abstract

The utility model belongs to the field of mass spectrum detection, and particularly relates to a mass spectrometer. The mass spectrometer comprises a rack; the vacuum cavity is mounted on the rack; the molecular pump is mounted on the vacuum cavity and is communicated with the vacuum cavity so as to vacuumize the interior of the vacuum cavity; the backing pump is mounted on the rack, the backing pump is communicated with the molecular pump so as to vacuumize the interior of the vacuum cavity, and an included angle is formed between the axis of the backing pump and the axis of the molecular pump. The included angle is formed between the axis of the backing pump and the axis of the molecular pump, that is, the axis of the backing pump is not parallel to the axis of the molecular pump, so that the resonant frequency of the backing pump and the resonant frequency of the molecular pump are staggered, resonance of the backing pump and the molecular pump is reduced, abnormal sound is eliminated, the stability of the molecular pump is improved, and abrasion of the molecular pump is reduced. Therefore, the product performance of the mass spectrometer is improved and the service life of the mass spectrometer is prolonged.

Description

Technical Field

[0001] This utility model belongs to the field of mass spectrometry detection, and in particular relates to a mass spectrometer. Background Technology

[0002] Mass spectrometers, as commonly used sample detection and analysis equipment, require a vacuum environment to be created for the sample. Currently, this is generally achieved by using a backing pump and a molecular pump in conjunction to evacuate the vacuum chamber inside the mass spectrometer. However, the backing pump and molecular pump of traditional mass spectrometers are prone to resonance, which can cause abnormal noises, lead to eccentricity or wear of the molecular pump, and reduce its service life. Utility Model Content

[0003] In view of the shortcomings of the prior art described above, the purpose of this utility model is to provide a mass spectrometer to solve the problem of resonance between the backing pump and the molecular pump in the prior art, which causes abnormal noise, so as to reduce resonance, improve the product performance of the mass spectrometer and extend its service life.

[0004] To achieve the above and other related objectives, this utility model provides a mass spectrometer, comprising:

[0005] frame;

[0006] A vacuum chamber, which is mounted on the frame;

[0007] A molecular pump is mounted on and connected to the vacuum chamber to evacuate the interior of the vacuum chamber.

[0008] A backing pump is mounted on the frame and is connected to the molecular pump to evacuate the interior of the vacuum chamber. The axis of the backing pump is at an angle to the axis of the molecular pump.

[0009] Optionally, the angle between the axis of the back pump and the axis of the molecular pump is 90°.

[0010] Optionally, the axis of the back pump is parallel to the vertical direction, and the axis of the molecular pump is parallel to the horizontal direction.

[0011] Optionally, the forepump is connected to the frame via a mounting bracket assembly.

[0012] Optionally, the mounting bracket assembly includes a frame and a buffer, the forepump is mounted on the frame, and the frame is mounted on the rack via the buffer.

[0013] Optionally, the frame includes a horizontal section and a vertical section connected together. The horizontal section is connected to the frame via the buffer, and the vertical section is connected to the pre-pump via a fixing structure.

[0014] Optionally, the buffer element is a buffer spring, the horizontal part is square, and the buffer spring is connected to each of the four apex corners of the horizontal part.

[0015] Optionally, the forepump has a first operating mode and a second operating mode, wherein the operating voltage of the first operating mode is higher than the operating voltage of the second operating mode; the mass spectrometer further includes a control circuit, which has a forepump voltage control module and a molecular pump speed information acquisition module, wherein the forepump voltage control module controls the forepump to switch between the first operating mode and the second operating mode according to the speed information of the molecular pump acquired by the molecular pump speed information acquisition module;

[0016] When the operating speed of the molecular pump is less than the rated speed, the backing pump is in the first operating mode; when the operating speed of the molecular pump is equal to the rated speed, the backing pump is in the second operating mode.

[0017] Optionally, the operating voltage of the back pump in the first working mode is U1, where 5V≤U1<10V or 10V≤U1≤20V, and the operating voltage of the back pump in the second working mode is U2, where 2V≤U2<3V or 3V≤U2≤5V, and 1<U1:U2≤5.

[0018] Optionally, the forepump includes a mechanical pump or a diaphragm pump; and / or, the molecular pump includes a turbomolecular pump.

[0019] As described above, the mass spectrometer of this invention has at least the following beneficial effects: the axis of the fore-pump is at an angle to the axis of the molecular pump, that is, the axis of the fore-pump is not parallel to the axis of the molecular pump, so that the resonant frequencies of the fore-pump and the molecular pump are staggered, which helps to reduce the resonance of the fore-pump and the molecular pump, thereby helping to eliminate abnormal noise, improve the stability of the molecular pump, reduce the wear of the molecular pump, and thus help to improve the product performance of the mass spectrometer and extend the service life of the mass spectrometer.

[0020] To achieve the above and other related objectives, this application also provides a mass spectrometer, comprising:

[0021] frame;

[0022] A vacuum chamber, which is mounted on the frame;

[0023] A molecular pump is mounted on and connected to the vacuum chamber to evacuate the interior of the vacuum chamber.

[0024] A backing pump is mounted on the frame and is connected to the molecular pump to evacuate the interior of the vacuum chamber. The backing pump has a first operating mode and a second operating mode, wherein the operating voltage of the first operating mode is higher than the operating voltage of the second operating mode.

[0025] The control circuit includes a pre-pump voltage control module and a molecular pump speed information acquisition module. The pre-pump voltage control module controls the pre-pump to switch between the first working mode and the second working mode based on the speed information of the molecular pump acquired by the molecular pump speed information acquisition module.

[0026] When the operating speed of the molecular pump is less than the rated speed, the backing pump is in the first operating mode; when the operating speed of the molecular pump is equal to the rated speed, the backing pump is in the second operating mode.

[0027] As described above, the mass spectrometer of this invention has at least the following beneficial effects: by adjusting the voltage of the fore-pump to change the rotation speed of the fore-pump, the amplitude of the fore-pump can be adjusted. In particular, when reducing the amplitude of the fore-pump, it is beneficial to reduce the resonance between the fore-pump and the molecular pump, thereby helping to eliminate abnormal noise, improve the stability of the molecular pump, reduce the wear of the molecular pump, and thus help to improve the product performance of the mass spectrometer and extend the service life of the mass spectrometer. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0029] Figure 1 This is a schematic diagram of the structure of an embodiment of the mass spectrometer of this utility model;

[0030] Figure 2 for Figure 1 A magnified schematic diagram of part A in the middle.

[0031] Part Number Explanation

[0032] Frame 1, vacuum chamber 2, molecular pump 3, backing pump 4, mounting bracket assembly 5, frame 51, buffer 52, fixing structure 53. Detailed Implementation

[0033] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0034] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0035] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0036] See Figure 1 and Figure 2 In some optional embodiments, this application provides a mass spectrometer including a frame 1, a vacuum chamber 2, a molecular pump 3, and a backing pump 4. The vacuum chamber 2 is mounted on the frame 1 and is used for sample ionization, ion flight, and mass spectrometry detection; the molecular pump 3 is mounted on the vacuum chamber 2 and communicates with the vacuum chamber 2 to evacuate the interior of the vacuum chamber 2; the backing pump 4 is mounted on the frame 1 and communicates with the molecular pump 3 to evacuate the interior of the vacuum chamber 2.

[0037] Optionally, the backing pump 4 may include a mechanical pump or a diaphragm pump.

[0038] Optionally, the molecular pump 3 includes a turbomolecular pump.

[0039] In the mass spectrometer of the above embodiment, the forepump 4 and the molecular pump 3 work together to effectively achieve vacuuming of the vacuum chamber 2.

[0040] See Figure 1 and Figure 2In some optional embodiments, the axis of the back pump 4 is at an angle to the axis of the molecular pump 3. That is, the axis of the back pump 4 is not parallel to the axis of the molecular pump 3, or the direction of the axis of the back pump 4 is different from the direction of the axis of the molecular pump 3. This causes the resonant frequencies of the back pump 4 and the molecular pump 3 to be misaligned, which helps to eliminate abnormal noise.

[0041] Optionally, the angle between the centerline of the backing pump 4 and the centerline of the molecular pump 3 is 90°. Further, the centerline of the backing pump 4 is parallel to the vertical direction, and the centerline of the molecular pump 3 is parallel to the horizontal direction. Specifically, in this application, the backing pump 4 and the molecular pump 3 are arranged along the Y-direction, the centerline of the backing pump 4 is parallel to the Z-direction, and the centerline of the molecular pump 3 is parallel to the X-direction.

[0042] In the mass spectrometer of the above embodiment, the axis of the forepump 4 is not parallel to the axis of the molecular pump 3, or in other words, the axis of the forepump 4 and the axis of the molecular pump 3 are arranged in different directions. That is, the installation directions of the forepump 4 and the molecular pump 3 are different, which makes the resonant frequencies of the forepump 4 and the molecular pump 3 staggered. This helps to reduce the resonance of the forepump 4 and the molecular pump 3 and eliminate abnormal noise. Especially for the molecular pump 3, the continuous high speed operation of the molecular pump 3 makes it easy for vibration to cause abnormal noise. By changing the layout of the forepump 4 and the molecular pump 3 to reduce their resonance, it is very effective in eliminating the abnormal noise of the molecular pump 3. This makes the structure of the molecular pump 3 more stable, which can not only operate at high speed continuously, but is also less prone to eccentricity and wear, which helps to extend its service life. In addition, it helps to improve the product performance of the mass spectrometer and extend the service life of the mass spectrometer.

[0043] See Figure 1 and Figure 2 In some alternative embodiments, the fore-pump 4 is connected to the frame 1 via a mounting bracket assembly 5.

[0044] Optionally, the mounting bracket assembly 5 includes a frame 51 and a buffer 52. The fore-pump 4 is mounted on the frame 51, and the frame 51 is mounted on the frame 1 via the buffer 52. Further, the frame 51 includes a connected horizontal section and a vertical section. For example, the frame 51 can be L-shaped. The horizontal section is connected to the frame 1 via the buffer 52, and the vertical section is connected to the fore-pump 4 via a fixing structure 53. Specifically, the buffer 52 can be a buffer spring. The horizontal section is square, and buffer springs are connected to the four corners of the horizontal section, resulting in uniform force distribution, structural stability, and good buffering effect, which helps to reduce the vibration of the fore-pump 4 and decrease its amplitude. The fixing structure 53 includes bolts that lock the fore-pump 4 to the vertical section.

[0045] In the mass spectrometer described above, the connection between the back pump 4 and the mounting bracket is simple and convenient, which helps to reduce the installation difficulty of the back pump 4. Moreover, the buffer 52 can reduce the amplitude of the back pump 4. Reducing the amplitude not only helps to reduce the risk of abnormal noise from the back pump 4, but also helps to reduce the impact of the amplitude of the back pump 4 on the molecular pump 3, reducing the resonance amplitude, thereby helping to reduce the risk of abnormal noise from the molecular pump 3. Especially when only the back pump 4 is operating, the back pump 4 needs to run at a high speed, and the buffer 52 can effectively buffer the vibration of the back pump 4.

[0046] See Figure 1 and Figure 2 In some optional embodiments, the forepump 4 has a first operating mode and a second operating mode, with the operating voltage of the first operating mode being higher than that of the second operating mode. The mass spectrometer also includes a control circuit, which has a forepump voltage control module and a molecular pump speed information acquisition module. The forepump voltage control module controls the forepump to switch between the first and second operating modes based on the speed information of the molecular pump acquired by the molecular pump speed information acquisition module. When the operating speed of the molecular pump 3 is less than the rated speed, the forepump 4 is in the first operating mode; when the operating speed of the molecular pump 3 is equal to the rated speed, the forepump 4 is in the second operating mode. It can be understood that the operating voltage of the forepump 4 is proportional to its speed, and the operating voltage of the molecular pump 3 is also proportional to its speed; that is, as the operating voltage decreases, the speed will decrease accordingly.

[0047] Optionally, the operating voltage of the backing pump 4 in the first operating mode is U1, where 5V≤U1<10V or 10V≤U1≤20V; and the operating voltage of the backing pump 4 in the second operating mode is U2, where 2V≤U2<3V or 3V≤U2≤5V, and 1<U1:U2≤5. The operating voltage U1 of the backing pump 4 in the first operating mode is the rated voltage.

[0048] Specifically, during mass spectrometry operation, the forepump 4 is started first, evacuating the vacuum chamber 2 to the preset vacuum level. Then, the molecular pump 3 is started, and the molecular pump 3 and forepump 4 work together to evacuate the vacuum chamber 2. During the evacuation process, the operating speed of the molecular pump 3 gradually increases to its rated speed (i.e., full speed). When the operating speed of the molecular pump 3 reaches its rated speed, the operating voltage of the forepump 4 can be reduced to decrease its operating speed. This further mitigates the impact of the vibration of the forepump 4 on the molecular pump 3, making the molecular pump 3 less prone to abnormal noise. For example, in the first operating mode, when the molecular pump 3 is not running or has not reached its rated speed, the forepump 4 can operate at an operating voltage U1 of 10V. In the second operating mode, when the molecular pump 3 reaches its rated speed, the forepump 4 can reduce its operating voltage to decrease the operating speed, thereby reducing the amplitude. In this embodiment, the operating voltage U2 of the forepump 4 in the second operating mode can be 3V. At this time, the low-frequency resonant amplitude of the molecular pump 3 along its axis can be reduced from 140 to 20, and the molecular pump 3 makes no abnormal noise. It is understood that the operating voltage of the forepump 4 in the first and second operating modes is not limited to the 10V and 3V examples mentioned above; the specific operating voltage value can be adjusted according to requirements.

[0049] In the mass spectrometer of the above embodiment, the forepump 4 has different operating modes to adapt to the different operating states of the molecular pump 3, which helps to reduce resonance with the molecular pump 3 and makes the molecular pump 3 less prone to abnormal noise.

[0050] In this mass spectrometer, the forepump 4 and the molecular pump 3 work together to evacuate the vacuum chamber 2, enabling the chamber 2 to quickly reach and maintain a vacuum state. Based on this, by changing the arrangement of the forepump 4 and the molecular pump 3 to reduce their resonance, and / or by controlling the voltage of the forepump to change the amplitude of the forepump 4 to reduce the resonance between the forepump 4 and the molecular pump 3, it is beneficial to reduce or even eliminate abnormal noise from the molecular pump 3, making it less prone to eccentricity and wear, thus improving the performance of the mass spectrometer and extending its service life.

[0051] In the description of this specification, the references to terms such as "this embodiment," "example," and "specific example" refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0052] The above are merely embodiments of this application and do not limit the scope of this patent application. Any equivalent structural or procedural changes made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of this application.

Claims

1. A mass spectrometer, characterized in that, include: frame; A vacuum chamber, which is mounted on the frame; A molecular pump is mounted on and connected to the vacuum chamber to evacuate the interior of the vacuum chamber. A backing pump is mounted on the frame and is connected to the molecular pump to evacuate the interior of the vacuum chamber. The axis of the backing pump is at an angle to the axis of the molecular pump.

2. The mass spectrometer according to claim 1, characterized in that, The angle between the axis of the back pump and the axis of the molecular pump is 90°.

3. The mass spectrometer according to claim 2, characterized in that, The axis of the forepump is parallel to the vertical direction, and the axis of the molecular pump is parallel to the horizontal direction.

4. The mass spectrometer according to any one of claims 1 to 3, characterized in that, The fore-pump is connected to the frame via a mounting bracket assembly.

5. The mass spectrometer according to claim 4, characterized in that, The mounting bracket assembly includes a frame and a buffer, the fore-pump is mounted on the frame, and the frame is mounted on the rack via the buffer.

6. The mass spectrometer according to claim 5, characterized in that, The frame includes a horizontal section and a vertical section connected together. The horizontal section is connected to the frame through the buffer member, and the vertical section is connected to the pre-pump through a fixing structure. The buffer member is a buffer spring. The horizontal section is square, and the buffer spring is connected to each of the four apex corners of the horizontal section.

7. The mass spectrometer according to any one of claims 1 to 3, characterized in that, The forepump has a first operating mode and a second operating mode, wherein the operating voltage of the first operating mode is higher than that of the second operating mode; the mass spectrometer further includes a control circuit, which has a forepump voltage control module and a molecular pump speed information acquisition module. The forepump voltage control module controls the forepump to switch between the first operating mode and the second operating mode according to the speed information of the molecular pump acquired by the molecular pump speed information acquisition module. When the operating speed of the molecular pump is less than the rated speed, the backing pump is in the first operating mode; when the operating speed of the molecular pump is equal to the rated speed, the backing pump is in the second operating mode.

8. The mass spectrometer according to claim 7, characterized in that, The operating voltage of the pre-pump in the first working mode is U1, where 5V≤U1<10V or 10V≤U1≤20V. The operating voltage of the pre-pump in the second working mode is U2, where 2V≤U2<3V or 3V≤U2≤5V, and 1<U1:U2≤5.

9. The mass spectrometer according to any one of claims 1 to 3, characterized in that, The forepump includes a mechanical pump or a diaphragm pump; and / or, the molecular pump includes a turbomolecular pump.

10. A mass spectrometer, characterized in that, include: frame; A vacuum chamber, which is mounted on the frame; A molecular pump is mounted on and connected to the vacuum chamber to evacuate the interior of the vacuum chamber. A backing pump is mounted on the frame and is connected to the molecular pump to evacuate the interior of the vacuum chamber. The backing pump has a first operating mode and a second operating mode, wherein the operating voltage of the first operating mode is higher than the operating voltage of the second operating mode. The control circuit includes a pre-pump voltage control module and a molecular pump speed information acquisition module. The pre-pump voltage control module controls the pre-pump to switch between the first working mode and the second working mode based on the speed information of the molecular pump acquired by the molecular pump speed information acquisition module. When the operating speed of the molecular pump is less than the rated speed, the backing pump is in the first operating mode; when the operating speed of the molecular pump is equal to the rated speed, the backing pump is in the second operating mode.

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