An electrode rod and multipole assembly for multipole ion transport

Abstract

This invention provides an electrode rod for multipole ion transport, comprising a rod body. In a cross-section perpendicular to the axis of the rod body, the rod body includes a curved section, a mounting section, and a transition section for extending the distance between the curved section and the mounting section. The curved section has a bent surface for forming an electrode field. The mounting section is located opposite to the bent surface and is used for positioning and mounting. The transition section extends along the opposite direction of the bent surface and connects to the mounting section. A multipole assembly is also provided, including a fixing member and at least two pairs of electrode rods positioned and mounted by the fixing member. This invention provides an electrode rod and a multipole assembly for multipole ion transport, ensuring both convenient installation and ion focusing capability when the number of electrode rods increases.

Description

Technical Field

[0001] This invention relates to the field of analytical testing instrument technology, specifically to an electrode rod and multipole assembly for multipole ion transport. Background Technology

[0002] Mass spectrometry is a strategic core technology in developed countries, involving the theoretical and technological development of basic disciplines such as physics, chemistry, biology, and medicine, as well as comprehensive scientific and technological fields such as computer technology, measurement science and technology, informatics and artificial intelligence, and high-precision instrument manufacturing. Due to its high sensitivity, high accuracy, speed, and versatility, mass spectrometry analysis is widely used in many scientific research and daily life fields. In recent years, with the further deepening of scientific research in life sciences, materials science, and environmental protection, and the significant improvement in people's material living standards, the level of mass spectrometry analysis technology has been continuously improving, and its application areas have become increasingly broad.

[0003] Of all types of mass spectrometry, tandem mass spectrometry (TMS) has the greatest demand. A tandem mass spectrometer is a mass spectrometer that connects two or more mass analyzers together. The ion source in a tandem mass spectrometer typically operates at atmospheric pressure, while the detector usually operates in a high vacuum region. An ion lens is needed between these two locations for ion transport. In 1952, Professor Wolfgang Paul and others from the Department of Physics at the University of Bonn, Germany, proposed the idea of ​​using a radio frequency quadrupole electric field to filter ions and experimentally verified it.

[0004] Multipole systems are increasingly used for ion transport. These systems mainly include quadrupoles, hexapoles, octopoles, and dodecoles. For ease of manufacturing, circular rods are often used instead of ideal curved rods. When using multipole systems as ion transport devices, ion transport efficiency must be considered, and the ion channel area (i.e., the inscribed circle of the multipole) significantly affects this efficiency. When the ion channel area decreases, the rod radius decreases, improving focusing ability; however, this leads to a shorter rod spacing, increasing the likelihood of discharge phenomena. Furthermore, a smaller rod radius hinders rod installation, especially with a higher number of rods. Conversely, a larger ion channel area increases the rod spacing, making installation easier, but weakens the multipole's focusing ability. Therefore, it is difficult to guarantee a multipole kit that can be easily installed without weakening the multipole field's focusing ability, preventing inter-rod discharge phenomena, and facilitating installation. Summary of the Invention

[0005] I. Technical problems to be solved

[0006] To address the shortcomings of existing technologies, this invention provides an electrode rod and multi-pole kit for multi-pole ion transport, overcoming the problems of existing multi-pole installation, ion focusing capability, and inter-pole discharge.

[0007] II. Technical Solution

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] An electrode rod for multipole ion transport is characterized by comprising a rod body, wherein, in a cross-section perpendicular to the axis of the rod body, the rod body includes a curved section, a mounting section, and a transition section for extending the distance between the curved section and the mounting section. The curved section is provided with a curved surface for forming an electrode field. The mounting section is located opposite to the curved surface and is used for positioning and mounting. The transition section extends along the opposite direction of the curved surface and connects to the mounting section.

[0010] Optionally, the transition portion includes two lateral surfaces for transitioning from both sides of the curved surface to both sides of the mounting portion, the two lateral surfaces being symmetrically arranged, and both lateral surfaces being concave curved surfaces.

[0011] Optionally, the width of the mounting portion is greater than the width of the curved surface.

[0012] Optionally, the outer surface of the mounting portion includes an arc segment and a rounded corner segment. The two ends of the arc segment are connected to the lateral surface through the rounded corner segment. The maximum width of the mounting portion is the maximum distance between the outer ends of the two rounded corner segments.

[0013] A multi-pole assembly is also provided, the key feature of which is that it includes: a fixing member and at least two pairs of electrode rods as described in any of the above examples, which are positioned and mounted by the fixing member;

[0014] The electrode rods are arranged in parallel along their axes. The electrode rods are evenly distributed circumferentially along the inscribed circle on a plane perpendicular to the axis of the electrode rod. The mounting part of the electrode rod is positioned and installed with the fixing member. The curved part of the electrode rod is tangent to the inscribed circle and faces the center of the inscribed circle. The two electrode rods in each pair are symmetrically arranged. The minimum distance between the curved parts of two adjacent electrode rods is the minimum distance between adjacent electrode rods.

[0015] Optionally, the fixing component is a ceramic ring. The inner wall of the ceramic ring is uniformly provided with mounting grooves corresponding to the number of electrode rods along the circumferential direction. The mounting part of the electrode rod is inserted into the mounting groove one by one along the axial direction of the ceramic ring. The inner surface of the mounting groove is in contact with the outer surface of the mounting part. The width of the groove through the transition part is less than the maximum width of the mounting groove, which is used to radially limit the electrode rod.

[0016] Optionally, the fixing member and the mounting part of each electrode rod are provided with corresponding connecting holes, and the fixing member and the mounting part are fitted with locking members and locked in place through the connecting holes.

[0017] Optionally, the curved surface of the curved surface is an arc surface, or the curved surface of the curved surface is a hyperboloid formed by two arc surfaces of the same radius symmetrically distributed.

[0018] Optionally, the curved surface of the curved surface is an arc surface, and the radius of the arc surface is adjusted according to the radius of the inscribed circle of the required electrode field and the number of electrode rods by a standard multiple.

[0019] Optionally, when the number of electrode rods is two, three, four, or six pairs, they correspond to four-pole, six-pole, eight-pole, and twelve-pole structures.

[0020] Quadrupole: The radius R of the curved surface is 1.12 to 1.15 times the radius R0 of the inscribed circle, and the central angle of the curved surface is 60 to 90°.

[0021] Hexapole: The radius R of the curved surface is 0.52 to 0.55 times the radius R0 of the inscribed circle, and the central angle of the curved surface is 70 to 120°.

[0022] Eight-pole rod: The radius R of the curved surface is 0.34 to 0.37 times the radius R0 of the inscribed circle, and the central angle of the curved surface is 80 to 135°.

[0023] Twelve poles: The radius R of the curved surface is 0.14 to 0.17 times the radius R0 of the inscribed circle, and the central angle of the curved surface is 90 to 150°.

[0024] III. Beneficial Effects

[0025] 1. The electrode rod of this application extends the distance between the curved part and the mounting part through the transition part. The curved part is used to generate the electrode field, and the mounting part is used for installation, thereby separating the functions of forming the electrode field and installation. The size of the curved part does not limit the size of the transition part and the mounting part. Moreover, during the design, the length of the transition part can be appropriately extended according to the installation space required by the mounting part. The longer the transition part, the farther the distance between the mounting part and the curved part, and the larger the installation space of the mounting part.

[0026] 2. When applied to form a multi-electrode, as the number of electrode rods increases, the mounting part is used for positioning and installation with the fixing parts to ensure that the adjacent electrode rods of the multi-electrode can maintain a safe distance and prevent discharge. The curved surface can be selected with a suitable radius according to the standard requirements of the multiple of the inscribed circle radius to ensure the ion focusing capability. Thus, there is no need to consider whether the installation is convenient due to the curved surface being too small. This achieves both convenient installation of the electrode rod and guaranteed ion focusing capability. Attached Figure Description

[0027] Figure 1This is a schematic diagram of the structure of an electrode rod for multipole ion transport according to the present invention;

[0028] Figure 2 This is a schematic diagram of the multipole structure formed by the electrode rod assembly of the present invention;

[0029] Figure 3 This is a schematic diagram of the quadrupole assembly.

[0030] Figure 4 for Figure 3 Schematic diagram of the middle fixing component;

[0031] Figure 5 A 3D view of a quadrupole assembly;

[0032] Figure 6 A 3D view of a six-pole lever assembly;

[0033] Figure 7 A 3D view of an octagonal lever assembly;

[0034] Figure 8 A 3D view of a twelve-pole assembly;

[0035] Wherein 1-electrode rod; 101-curved surface; 102-mounting part; 103-transition part; 104-bent surface; 105-lateral surface; 106-arc segment; 107-rounded corner segment; 2-fixing component; 201-mounting groove; 202-connection hole. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] Figure 1 This is a schematic diagram illustrating the structure of an electrode rod for multipole ion transport, as shown in an exemplary embodiment of the present invention. Figure 1 As shown: An electrode rod for multipole ion transport includes a rod body. In a cross-section perpendicular to the axis of the rod body, the rod body includes a curved surface 101, a mounting portion 102, and a transition portion 103 for extending the distance between the curved surface 101 and the mounting portion 102. The curved surface 101, the mounting portion 102, and the transition portion 103 are preferably integrally formed. The curved surface 101 is provided with a curved surface 104 for forming an electrode field. The mounting portion 102 is located opposite to the curved surface 104 and is used for positioning and mounting. The transition portion 103 extends along the opposite side of the curved surface 104 and connects to the mounting portion 102.

[0038] Please see the appendix Figure 1 The transition portion 103 includes two lateral surfaces 105 for transitioning from both sides of the curved surface 104 to both sides of the mounting portion 102. The two lateral surfaces 105 are symmetrically arranged, and both lateral surfaces 105 are concave curved surfaces. After the multi-pole rod is assembled, a safe distance is fully guaranteed in the transition portion 103 area of ​​adjacent electrode rods, and no discharge phenomenon will occur.

[0039] Please see the appendix Figure 1 Given sufficient installation space, a wider mounting portion 102 is easier to install than a narrower one. Therefore, choosing a width greater than the width of the curved surface 101 yields better results. The outer surface of the mounting portion 102 includes an arc segment 106 and a rounded corner segment 107. The two ends of the arc segment 106 are connected to the lateral surface via the rounded corner segment 107. The maximum width of the mounting portion 102 is the maximum distance between the outer ends of the two rounded corner segments 107.

[0040] The arc segment 106 of the mounting part 102 and the rounded corner segments 107 at both ends can be combined to form a semi-circle.

[0041] The arc segment 106 and the rounded corner segments 107 at both ends can also be combined to form a semi-ellipse. Since the semi-circular mounting part is prone to circumferential displacement and rotation during installation, the semi-elliptical mounting part has better circumferential installation stability than the semi-circular part. However, the semi-circular mounting part can solve the displacement and rotation problem by positioning and fixing it with the fastener.

[0042] Alternatively, the outer surface of the mounting part 102 can also be made of other polygonal shapes, as long as they are easy to process and install.

[0043] Please see the appendix Figure 2 A multipole assembly can be configured as a quadrupole, hexapole, octapole, or dodecapole based on the logarithmic combination of electrode rods. The arrangement is as follows: Figure 2 As shown, a represents the arrangement of quadrupoles, b represents the arrangement of hexapoles, c represents the arrangement of octapoles, and d represents the arrangement of dodecapoles.

[0044] Figure 3 and 5 The diagram and perspective view show a quadrupole assembly as an exemplary embodiment of the present invention.

[0045] like Figure 3 and 5As shown: A quadrupole assembly includes at least two pairs of electrode rods 1 and a fixing member 2 for positioning the electrode rods 1; the electrode rods 1 are the electrode rods 1 shown in any of the above examples. The curved surface 104 of the curved portion 101 of the electrode rod 1 is an arc surface, the radius R of which is 1.12-1.15 times the radius R0 of the inscribed circle, and the central angle X1 corresponding to the arc surface is 90°.

[0046] It should be noted that for the quadrupole kit, the angle between the center line connecting electrode rod 1 and the center line connecting the two adjacent electrode rods 1 is 90°. The intersection point of the center line and the edge of the curved surface 101 is the point where the distance between adjacent electrode rods 1 is the smallest. Therefore, when the center angle corresponding to the curved surface is less than 90°, the radius remains unchanged, the width of the curved surface decreases, and the distance between adjacent electrode rods 1 further increases. However, in order to ensure that a stable polar field is formed between adjacent curved surfaces, the width of the curved surface cannot be too small. Therefore, the center angle corresponding to the curved surface cannot be less than 60°, and the center angle X1 degree corresponding to the curved surface can be selected between 60° and 90°.

[0047] Please see the appendix Figure 3 and 5 The electrode rods 1 are arranged in parallel along their axes. The electrode rods 1 are evenly distributed along the circumference of the inscribed circle on a plane perpendicular to the axis of the electrode rod 1. The mounting part 102 of the electrode rod 1 is positioned and installed with the fixing member 2. The curved part 101 of the electrode rod 1 is tangent to the inscribed circle and faces the center of the inscribed circle. The two electrode rods 1 in each pair are symmetrically arranged. The minimum distance between the curved parts 101 of two adjacent electrode rods 1 is the minimum distance between adjacent electrode rods 1.

[0048] Please see the appendix Figure 4 The fixing member 2 is made of insulating material, preferably a ceramic ring. The inner wall of the ceramic ring is uniformly provided with mounting grooves 201 corresponding to the number of electrode rods 1 along the circumference. The mounting part 102 of the electrode rod 1 is inserted into the mounting groove 201 one by one along the axial direction of the ceramic ring. The inner surface of the mounting groove 201 is in contact with the outer surface of the mounting part 102. The width of the groove 201 is smaller than the maximum width of the mounting groove 201, which is used to radially limit the electrode rod.

[0049] Please see the appendix Figure 5 The fixing member 2 and the mounting part 102 of each electrode rod 1 are respectively provided with a connection hole 202. The fixing member 2 and the mounting part 102 are fitted with a locking member and locked in place.

[0050] Figure 6 This is a schematic diagram of the structure of a hexapole kit shown in an exemplary embodiment of the present invention.

[0051] like Figure 6 and combined Figure 2 As shown in b: The six-pole assembly and the four-pole assembly are identical in structure, except for the difference in the number and size of the electrode rods 1 and the number of mounting slots 201 of the fixing parts 2. The number of electrode rods 1 is three pairs. With the inscribed circle radius R0 remaining constant, the curved surface 104 of the curved part 101 of the electrode rod 1 adopts an arc surface. The radius R of this arc surface is 0.52-0.55 times the inscribed circle radius R0, and the central angle X2 corresponding to this arc surface is 120°.

[0052] It should be noted that for the hexapole kit, the angle between the center line connecting electrode rod 1 and the center line connecting the two adjacent electrode rods 1 is 120°. The intersection point of the center line and the edge of the curved surface 101 is the point where the distance between adjacent electrode rods 1 is the smallest. Therefore, when the center angle corresponding to the curved surface is less than 120°, the radius remains unchanged, the width of the curved surface decreases, and the distance between adjacent electrode rods 1 further increases. However, in order to ensure that a stable electrode field is formed between adjacent curved surfaces, the width of the curved surface cannot be too small. Therefore, the center angle corresponding to the curved surface cannot be less than 70°. The center angle X2 degree corresponding to the curved surface can be selected between 70° and 120°.

[0053] Figure 7 This is a schematic diagram of the structure of an eight-pole lever assembly, as shown in an exemplary embodiment of the present invention.

[0054] like Figure 7 and combined Figure 2 As shown in c: The octupole kit and the quadrupole kit are identical in structure, except for the number and size of the electrode rods 1 and the number of mounting slots 201 of the fixing parts 2. The number of electrode rods 1 is four pairs. With the inscribed circle radius R0 remaining constant, the curved surface 104 of the curved part 101 of the electrode rod 1 adopts an arc surface. The radius R of this arc surface is 0.34-0.37 times the inscribed circle radius R0, and the central angle X3 corresponding to this arc surface is 135°.

[0055] It should be noted that for the octet rod kit, the angle between the center line connecting electrode rod 1 and the center line connecting the two adjacent electrode rods 1 is 135°. The intersection point of the center line and the edge of the curved surface 101 is the point where the distance between adjacent electrode rods 1 is the smallest. Therefore, when the center angle corresponding to the curved surface is less than 135°, the radius remains unchanged, the width of the curved surface decreases, and the distance between adjacent electrode rods 1 further increases. However, in order to ensure that a stable electrode field is formed between adjacent curved surfaces, the width of the curved surface cannot be too small. Therefore, the center angle corresponding to the curved surface cannot be less than 80°. The center angle X3 degree corresponding to the curved surface can be selected between 80° and 135°.

[0056] Figure 8This is a schematic diagram of the structure of a twelve-pole assembly as shown in an exemplary embodiment of the present invention.

[0057] like Figure 8 and combined Figure 2 As shown in d: The twelve-pole kit and the four-pole kit are completely identical in structure, except for the difference in the number and size of the electrode rods 1 and the number of mounting slots 201 of the fixing parts 2. The number of electrode rods 1 is six pairs. With the inscribed circle radius R0 remaining unchanged, the curved surface 104 of the curved part 101 of the electrode rod 1 adopts an arc surface. The radius R of this arc surface is 0.14 to 0.17 times the inscribed circle radius R0, and the central angle X4 corresponding to this arc surface is 150°.

[0058] It should be noted that for the octet rod kit, the angle between the center line connecting electrode rod 1 and the center line connecting the two adjacent electrode rods 1 is 150°. The intersection point of the center line and the edge of the curved surface 101 is the point where the distance between adjacent electrode rods 1 is the smallest. Therefore, when the center angle corresponding to the curved surface is less than 150°, the radius remains unchanged, the width of the curved surface decreases, and the distance between adjacent electrode rods 1 further increases. However, in order to ensure that a stable electrode field is formed between adjacent curved surfaces, the width of the curved surface cannot be too small. Therefore, the center angle corresponding to the curved surface cannot be less than 90°. The center angle X4 degree corresponding to the curved surface can be selected between 90° and 150°.

[0059] In any of the embodiments shown in the above examples, the curved surface 104 of the curved surface 101 may also be a hyperboloid formed by two arc surfaces with the same radius symmetrically distributed. The radius of the arc surface of the hyperboloid corresponds to the radius of one arc surface in the corresponding example above, and the width of the hyperboloid corresponds to the width of one arc surface in the corresponding example above.

[0060] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0061] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An electrode rod for multipole rod ion transmission, characterized by: The device includes a rod body. In a cross-section perpendicular to the axis of the rod body, the rod body includes a curved section, a mounting section, and a transition section for extending the distance between the curved section and the mounting section. The curved section has a curved surface for forming an electrode field. The mounting section is located opposite to the curved surface and is used for positioning and mounting. The transition section extends along the opposite side of the curved surface and connects to the mounting section. The transition section increases the mounting space of the mounting section. The width of the mounting section is greater than the width of the curved section. The outer surface of the mounting section includes an arc segment and a rounded corner segment. The two ends of the arc segment are connected to the transition section through the rounded corner segment. The maximum width of the mounting section is the maximum distance between the outer ends of the two rounded corner segments. After the multi-electrode rods are assembled, the minimum distance between the curved sections of two adjacent electrode rods is the minimum distance between adjacent electrode rods.

2. An electrode rod for use in ion transmission with a multipole rod as claimed in claim 1, characterized in that: The transition portion includes two lateral surfaces for transitioning from both sides of the curved surface to both sides of the mounting portion. The two lateral surfaces are symmetrically arranged, and both lateral surfaces are concave curved surfaces.

3. A multi-pole rod kit characterized by, include: The fastener and at least two pairs of electrode rods as described in any one of claims 1 to 2, which are positioned and installed by the fastener; The electrode rods are arranged in parallel along their axes. The electrode rods are evenly distributed circumferentially along the inscribed circle on a plane perpendicular to the axis of the electrode rod. The mounting part of the electrode rod is positioned and installed with the fixing member. The curved part of the electrode rod is tangent to the inscribed circle and faces the center of the inscribed circle. The two electrode rods in each pair are symmetrically arranged. The minimum distance between the curved parts of two adjacent electrode rods is the minimum distance between adjacent electrode rods.

4. A kit of multipole rods according to claim 3, characterized in that: The fixing component is a ceramic ring. The inner wall of the ceramic ring is uniformly provided with mounting grooves corresponding to the number of electrode rods along the circumference. The mounting part of the electrode rod is inserted into the mounting groove one by one along the axial direction of the ceramic ring. The inner surface of the mounting groove is in contact with the outer surface of the mounting part. The width of the groove through the transition part is less than the maximum width of the mounting groove, which is used to radially limit the electrode rod.

5. The multipole rod kit of claim 3, wherein: Each of the fixing components and the mounting portion of each electrode rod is provided with a corresponding connection hole. The fixing component and the mounting portion are fitted with locking components through the connection holes and locked in place.

6. The multi-pole rod assembly of any one of claims 3-5, wherein: The curved surface of the surface is an arc surface, or the curved surface of the surface is a hyperboloid formed by two arc surfaces of the same radius symmetrically distributed.

7. The multipole rod kit of claim 6, wherein: The curved surface of the curved surface is an arc surface, and the radius of the arc surface is adjusted according to the radius of the inscribed circle of the required electrode field and the number of electrode rods by a standard multiple.

8. The multipole rod kit of claim 7, wherein: When the number of electrode rods is two, three, four, or six pairs, they correspond to four-pole, six-pole, eight-pole, and twelve-pole structures, respectively. The radius R of the curved surface is 1.12 to 1.15 times, 0.52 to 0.55 times, 0.34 to 0.37 times, and 0.14 to 0.17 times the radius R0 of the inscribed circle, respectively. The central angles corresponding to the curved surface are 60 to 90°, 70 to 120°, 80 to 135°, and 90 to 150°, respectively.

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