Hydrogen flame ionization detector and gas chromatograph

Abstract

This application discloses a flame ionization detector and a gas chromatograph, belonging to the technical field of detection equipment. The gas chromatograph includes a flame ionization detector, which comprises: a mounting frame having a first reference surface; an inlet assembly including a first base and a nozzle mounted on the first base, the first base being connected to the mounting frame and having a first positioning surface facing the first reference surface and a second reference surface facing away from the first reference surface, the first positioning surface contacting the first reference surface, and the extension direction of the nozzle intersecting the first positioning surface; and an ion collection assembly including a second base and a collecting electrode mounted on the second base, the second base being connected to the mounting frame and having a second positioning surface contacting the second reference surface, and the collecting electrode and nozzle being positioned opposite each other. This detector can precisely control the relative position of the collecting electrode and the nozzle, thereby achieving high detection accuracy for organic compounds.

Description

Technical Field

[0001] This application belongs to the field of detection equipment technology, specifically relating to a hydrogen flame ionization detector and a gas chromatograph. Background Technology

[0002] A hydrogen flame ionization detector is a device that uses the flame generated by the combustion of hydrogen and air as an energy source to chemically ionize organic compounds and generate an electrical signal under the action of an electric field for detection.

[0003] The detector typically includes a nozzle and a collecting electrode positioned opposite each other. In the actual detection process, the sample gas containing organic compounds is ejected from the nozzle and burned to form a flame. The organic compounds in the sample gas are ionized at the high temperature of the flame and form an ion flow under the directional action of the high voltage electric field. The collecting electrode collects the ion flow, thereby performing quantitative analysis of the organic compounds in the sample gas.

[0004] In this detector, the relative position of the collecting electrode and the nozzle directly affects the detection accuracy of organic compounds. If they are too close, the collecting electrode will heat up, generating hot electrons and increasing noise. If they are too far apart, the time it takes for the ion current to reach the collecting electrode will be longer, resulting in poorer ion collection. However, the current control precision of the relative position of the collecting electrode and the nozzle is not good, which directly leads to low detection accuracy of organic compounds. Utility Model Content

[0005] The purpose of this application is to provide a hydrogen flame ionization detector and a gas chromatograph that can solve the problem of low detection accuracy of organic compounds in related technologies.

[0006] In a first aspect, embodiments of this application provide a hydrogen flame ionization detector, comprising:

[0007] Mounting bracket, having a first reference plane;

[0008] An air intake assembly includes a first base and a nozzle. The first base is connected to the mounting bracket, and the nozzle is mounted on the first base. The first base has a first positioning surface facing the first reference surface and a second reference surface facing away from the first reference surface. The first positioning surface is in contact with the first reference surface, and the extension direction of the nozzle intersects the first positioning surface.

[0009] An ion collection assembly includes a second base and a collecting electrode. The second base is connected to the mounting bracket, and the collecting electrode is mounted on the second base. The second base has a second positioning surface that contacts a second reference surface. The extending direction of the collecting electrode intersects the second positioning surface, and the collecting electrode is disposed opposite to the nozzle.

[0010] Secondly, embodiments of this application also provide a gas chromatograph, which includes the hydrogen flame ionization detector described above.

[0011] In related technologies, the two opposite sides of the mounting bracket in the thickness direction are a first reference surface and a second reference surface, respectively. The nozzle is mounted on a first base, which is positioned by the first reference surface. The collecting electrode is mounted on a second base, which is positioned by the second reference surface. In this layout, the first and second reference surfaces are located on opposite sides of the mounting bracket. The relative positional relationship between the collecting electrode and the nozzle is affected by the thickness of the mounting bracket. Once the thickness of the mounting bracket deviates, it will directly cause the relative position of the collecting electrode and the nozzle to shift, resulting in poor control accuracy of the relative position of the collecting electrode and the nozzle.

[0012] In this embodiment, the mounting bracket has a first reference surface, the first seat has a first positioning surface facing the first reference surface and a second reference surface facing away from the first reference surface, and the second seat has a second positioning surface. The first positioning surface is in contact with the first reference surface, and the second positioning surface is in contact with the second reference surface. With this configuration, the first seat is positioned by the first reference surface, and the second seat is positioned by the second reference surface, with both the first and second reference surfaces located on the same side of the mounting bracket. Therefore, the thickness of the mounting bracket does not affect the relative positions of the first and second seats. The nozzle is mounted on the first seat, and the collecting electrode is mounted on the second seat, so the thickness of the mounting bracket also does not affect the relative positions of the nozzle and the collecting electrode. Therefore, compared with solutions in related technologies, the solution in this embodiment can more accurately control the relative positions of the collecting electrode and the nozzle, resulting in higher detection accuracy for organic compounds. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the hydrogen flame ionization detector disclosed in the embodiments of this application;

[0014] Figure 2 for Figure 1 One of the schematic diagrams of a local structure;

[0015] Figure 3 for Figure 1 The second partial structural diagram;

[0016] Figure 4 This is a schematic diagram illustrating the assembly method of the collecting electrode and the nozzle as disclosed in an embodiment of this application;

[0017] Figure 5 This is a schematic diagram illustrating the mounting hole arrangement method disclosed in the embodiments of this application.

[0018] Explanation of reference numerals in the attached figures:

[0019] 100-Mounting bracket, 110-First reference plane, 120-Mounting hole, 121-Straight segment, 1211-Mounting port, 122-Arc segment;

[0020] 210-First seat, 211-Cylinder, 212-Annular mating part, 2121-First positioning surface, 2122-Second reference surface, 2123-Receiving groove, 2124-Second clearance groove, 220-Nozzle, 221-Second end face;

[0021] 310-Second seat, 311-Body, 3111-Second positioning surface, 3112-Mounting cavity, 3113-Limiting step, 312-Cylinder, 320-Collecting electrode, 321-Cylinder body, 3211-First end face, 322-Protrusion, 330-First insulator, 340-Second insulator;

[0022] 400 - Annular seal;

[0023] 510 - First threaded connector; 520 - Second locking component;

[0024] 600 - Cover, 610 - First clearance groove;

[0025] 700 - Heating mechanism;

[0026] 810 - First housing, 820 - Second housing. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0028] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0029] The hydrogen flame ionization detector and gas chromatograph provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0030] Please refer to Figures 1 to 5 As shown in the embodiment of this application, a hydrogen flame ionization detector is provided, which includes: a mounting bracket 100, an air intake assembly, and an ion collection assembly.

[0031] Specifically, the mounting bracket 100 has a first reference surface 110.

[0032] The air intake assembly includes a first base 210 and a nozzle 220. The first base 210 is connected to the mounting bracket 100, and the nozzle 220 is mounted on the first base 210. The first base 210 has a first positioning surface 2121 facing a first reference surface 110 and a second reference surface 2122 facing away from the first reference surface 110. The first positioning surface 2121 is in contact with the first reference surface 110, which serves as a positioning reference for the first base 210. The extension direction of the nozzle 220 intersects the first positioning surface 2121. Optionally, the extension direction of the nozzle 220 may be perpendicular to the first positioning surface 2121, for example.

[0033] The ion collection assembly includes a second base 310 and a collecting electrode 320. The second base 310 is connected to a mounting bracket 100. The collecting electrode 320 is mounted on the second base 310. The second base 310 has a second positioning surface 3111, which contacts a second reference surface 2122. The second reference surface 2122 serves as a positioning reference for the second base 310. The extending direction of the collecting electrode 320 intersects the second positioning surface 3111, and the collecting electrode 320 is positioned opposite to the nozzle 220. Optionally, the extending direction of the collecting electrode 320 may be perpendicular to the first positioning surface 2121, or it may be the same as the extending direction of the nozzle 220. Specifically, for example... Figure 3 The direction indicated by arrow A in the figure, and the extension direction of the collecting electrode 320 is, for example, the axial direction of the collecting electrode 320, and the extension direction of the nozzle 220 is, for example, the axial direction of the nozzle 220.

[0034] In related technologies, the two opposite sides of the mounting bracket in the thickness direction are a first reference surface and a second reference surface, respectively. The nozzle is mounted on a first base, which is positioned by the first reference surface. The collecting electrode is mounted on a second base, which is positioned by the second reference surface. In this layout, the first and second reference surfaces are located on opposite sides of the mounting bracket. The relative positional relationship between the collecting electrode and the nozzle is affected by the thickness of the mounting bracket. Once the thickness of the mounting bracket deviates, it will directly cause the relative position of the collecting electrode and the nozzle to shift, resulting in poor control accuracy of the relative position of the collecting electrode and the nozzle.

[0035] In this embodiment, the mounting bracket 100 has a first reference surface 110, the first base 210 has a first positioning surface 2121 facing the first reference surface 110 and a second reference surface 2122 facing away from the first reference surface 110, and the second base 310 has a second positioning surface 3111. The first positioning surface 2121 is in contact with the first reference surface 110, and the second positioning surface 3111 is in contact with the second reference surface 2122. With this configuration, the first base 210 is positioned by the first reference surface 110, and the second base 310 is positioned by the second reference surface 2122. Furthermore, the first reference surface 110 and the second reference surface 2122 are located on the same side of the mounting bracket 100. Therefore, the thickness of the mounting bracket 100 will not affect the relative position of the first base 210 and the second base 310. The nozzle 220 is installed on the first base 210 and the collecting electrode 320 is installed on the second base 310. Therefore, the thickness of the mounting bracket 100 will not affect the relative position of the nozzle 220 and the collecting electrode 320. Compared with the solutions in related technologies, the solution of this application embodiment can more accurately control the relative position of the collecting electrode 320 and the nozzle 220, thereby making the detection accuracy of organic compounds higher and reducing the performance difference between the two stages.

[0036] In addition, in this embodiment, the size of the mounting bracket 100 does not affect the relative position of the nozzle 220 and the collecting electrode 320, which reduces the requirements for the machining accuracy of the mounting bracket 100, thereby reducing the machining difficulty of the mounting bracket 100 and the machining cost of the mounting bracket 100.

[0037] In another embodiment, reference Figures 1 to 3 As shown, the first base 210 includes a cylindrical body 211. The first end of the cylindrical body 211 is disposed facing the second positioning surface 3111, and an annular fitting portion 212 is provided circumferentially around the first end of the cylindrical body 211. In other words, the annular fitting portion 212 is disposed around the first end of the cylindrical body 211. The first surface of the annular fitting portion 212 is disposed facing the first reference surface 110, and the second surface of the annular fitting portion 212 is disposed away from the first reference surface 110. The first surface and the second surface of the annular fitting portion 212 are opposite surfaces of the annular fitting portion 212 in the axial direction of the first base 210. The axial direction of the first base 210 is, for example, the same as the axial direction of the nozzle 220. The first positioning surface 2121 includes, for example, the first surface, and the second reference surface 2122 includes, for example, the second surface. The second end of the cylindrical body 211 passes through the mounting bracket 100 and extends out. At least a portion of the nozzle 220 is located in the inner cavity of the cylindrical body 211.

[0038] In this embodiment, a portion of the first base 210 is located on the side of the mounting bracket 100 opposite to the annular mating portion 212. This reduces the space occupied on the side of the mounting bracket 100 facing the annular mating portion 212, allowing that space to be used for the installation of other components. This layout optimizes space utilization, which helps improve the space utilization rate of the hydrogen flame ionization detector.

[0039] Furthermore, in this embodiment, at least a portion of the nozzle 220 is located within the inner cavity of the cylinder 211. In this arrangement, the cylinder 211 can protect the nozzle 220, thereby extending the service life of the nozzle 220.

[0040] Furthermore, the nozzle 220 is detachably connected to the cylinder 211, for example, to facilitate the replacement of the nozzle 220. Specifically, the outer wall of the nozzle 220 is threadedly connected to the inner wall of the cylinder 211, for example.

[0041] In other alternative embodiments, the first seat 210 may also be entirely located on the side of the mounting bracket 100 facing the annular mating portion 212. Additionally, the nozzle 220 may be located outside the cylinder 211.

[0042] In a further embodiment, reference is made to... Figures 1 to 3 As shown, the second seat 310 is provided with a mounting cavity 3112, at least a portion of the collecting electrode 320 is located in the mounting cavity 3112, and the mounting cavity 3112 is connected to the inner cavity of the cylinder 211 through the first end of the cylinder 211.

[0043] The hydrogen flame ionization detector also includes an annular seal 400. One of the second positioning surface 3111 and the second surface has a receiving groove 2123 extending along the centerline of the collecting electrode 320. The annular seal 400 is located in the receiving groove 2123 and is disposed around the first end of the cylinder 211. The annular seal 400 is in a sealing fit with both the first seat 210 and the second seat 310. The groove wall of the receiving groove 2123 can prevent the annular seal 400 from moving in a direction away from the centerline of the collecting electrode 320. This direction is, for example, perpendicular to the centerline of the collecting electrode 320, and this direction is, for example, perpendicular to the centerline of the collecting electrode 320. Figure 2 The direction indicated by arrow B in the diagram. Additionally, the direction of the center line of the collecting electrode 320 is, for example, the axial direction of the collecting electrode 320.

[0044] In this embodiment, the annular seal 400 seals the gap between the second positioning surface 3111 and the second surface, thereby reducing the probability of sample gas ejected from the nozzle 220 leaking through the gap between the second positioning surface 3111 and the second surface. Furthermore, the sample gas ejected from the nozzle 220 may include, for example, hydrogen gas. Hydrogen leakage can easily lead to an explosion; therefore, the solution in this embodiment also improves the safety of using the hydrogen flame ionization detector.

[0045] Furthermore, in this embodiment, the groove wall of the receiving groove 2123 can prevent the annular seal 400 from moving in a direction away from the center line of the collecting electrode 320. This restricts the movement of the annular seal 400 in a direction away from the center line of the collecting electrode 320, thereby improving the sealing effect. It should be noted that the outer side of the annular seal 400 is the low-pressure side, and the inner side is the high-pressure side. Under the pressure inside the cylinder 211, the annular seal 400 tends to move in a direction away from the center of the collecting electrode 320, that is, the annular seal 400 tends to move towards the low-pressure side.

[0046] Specifically, the groove wall of the receiving groove 2123 includes, for example, a first groove wall and a second groove wall disposed radially opposite to the annular seal 400. The outer side wall of the annular seal 400 contacts the first groove wall of the receiving groove 2123, while the inner side wall of the annular seal 400 has a gap with the second groove wall of the receiving groove 2123. Of course, in other embodiments, there may also be a gap between the outer side wall of the annular seal 400 and the first groove wall; similarly, the inner side wall of the annular seal 400 may also contact the second groove wall of the receiving groove 2123. The design can be tailored to actual needs.

[0047] Optionally, the receiving groove 2123 may be provided, for example, on the second surface of the annular mating portion 212. In this way, the provision of the receiving groove 2123 will not weaken the strength of the second seat 310, which extends the service life of the second seat 310.

[0048] Optionally, the annular seal 400 may include, for example, an elastic sealing ring. Additionally, the elastic sealing ring may be in a compressed state to ensure a tighter fit between the elastic sealing ring and both the first seat 210 and the second seat 310, thereby improving the sealing effect.

[0049] In other embodiments, the hydrogen flame ionization detector may also exclude the annular seal 400.

[0050] In a further embodiment, the collecting end of the collecting electrode 320 extends into the inner cavity of the cylinder 211 through the first end of the cylinder 211, and a portion of the nozzle 220 is located inside the collecting end of the collecting electrode 320.

[0051] In actual use, the sample gas containing organic compounds is ejected from the nozzle 220 and burned to form a flame. The organic compounds in the sample gas are ionized at the high temperature of the flame and form an ion flow under the directional action of the high voltage electric field. By placing a part of the nozzle 220 inside the collection end of the collection electrode 320, the collection electrode 320 can capture the ion flow better, which is beneficial to improving the detection accuracy of the hydrogen flame ionization detector.

[0052] Optionally, refer to Figure 1 and Figure 2As shown, the second seat 310 includes, for example, a body 311 and a cylindrical portion 312. The body 311 is located on the side of the annular mating portion 212 away from the mounting bracket 100 and has a mounting cavity 3112. The side of the body 311 facing the mounting bracket 100 is, for example, the second positioning surface 3111. One end of the cylindrical portion 312 is connected to the mounting cavity 3112, and the other end extends into the inner cavity of the cylindrical body 211 through the first end of the cylindrical body 211. The outer wall of the cylindrical portion 312 mates with the inner wall of the cylindrical body 211. The collecting end of the collecting electrode 320 passes through the cylindrical portion 312 and extends out. With this configuration, both the second positioning surface 3111 of the second seat 310 and the outer wall of the cylindrical portion 312 mate with the first seat 210, which gives the first seat 210 and the second seat 310 a large mating area, thereby making the mating between the first seat 210 and the second seat 310 more reliable.

[0053] Specifically, the outer wall of the cylindrical portion 312 may be clearance-fitted with the inner wall of the cylindrical body 211 to facilitate installation. Of course, the outer wall of the cylindrical portion 312 may also be transition-fitted or interference-fitted with the inner wall of the cylindrical body 211. In this embodiment, there is no limitation on this, and the design can be carried out according to actual needs.

[0054] In other embodiments, the nozzle 220 may also be entirely located outside the collecting electrode 320. Additionally, the second seat 310 may not include the cylindrical portion 312, but only the body 311.

[0055] In a further embodiment, reference is made to... Figure 5 As shown, the mounting bracket 100 is provided with a mounting hole 120 extending along the thickness direction of the mounting bracket 100. The thickness direction of the mounting bracket 100 is, for example, the same as the axial direction of the cylinder 211. The second end of the cylinder 211 passes through the mounting hole 120, and the mounting hole 120 penetrates the side wall of the mounting bracket 100 in a direction perpendicular to the thickness direction of the mounting bracket 100, forming a mounting opening 1211. Specifically, the mounting hole 120 penetrates the side wall of the mounting bracket 100 in the radial direction of the cylinder 211, forming a mounting opening 1211. The mounting opening 1211 allows a part of the cylinder 211 to enter and exit the mounting hole 120.

[0056] Using the solution of this embodiment, the first base 210 can be installed on the mounting frame 100 in a direction perpendicular to the thickness direction of the mounting frame 100, thereby satisfying the installation requirement that the first base 210 be installed in a direction perpendicular to the thickness direction of the mounting frame 100.

[0057] Hydrogen flame ionization detectors typically also include a heating mechanism 700, which heats the nozzle 220 to meet specific operational requirements. The heating mechanism 700 is usually located on the side of the mounting bracket 100 opposite to the annular mating portion 212 and is non-removably connected to the cylinder 211. Typically, the heating mechanism 700 must first be installed on the cylinder 211 before the first seat 210 is installed on the mounting bracket 100. However, the heating mechanism 700 is often large and cannot pass through the mounting hole 120 along the thickness direction of the mounting bracket 100. In such cases, for example, the solution of this embodiment can be used to install the first seat 210 and the heating mechanism 700 together in a direction perpendicular to the thickness direction of the mounting bracket 100. Specifically, for example, a portion of the cylinder 211 can be slid into the mounting hole 120 from the mounting opening 1211 in a direction perpendicular to the thickness direction of the mounting bracket 100, thus completing the overall installation of the first seat 210 and the heating mechanism 700.

[0058] In other embodiments, the mounting port 1211 may be omitted. In this case, for example, the size of the mounting hole 120 needs to be adjusted so that the heating mechanism 700 can pass through the mounting hole 120 to achieve the overall installation of the first base 210 and the heating mechanism 700. Alternatively, the heating mechanism 700 can also be detachably connected to the cylinder 211. Specifically, the heating mechanism 700 may have a threaded component, which abuts against the cylinder 211 to detachably connect the heating mechanism 700 to the cylinder 211.

[0059] In a further embodiment, reference is made to... Figure 5 As shown, the mounting hole 120 includes, for example, a straight segment 121 and an arc-shaped segment 122. The mounting opening 1211 includes a port at one end of the straight segment 121, and the other end of the straight segment 121 is connected to the arc-shaped segment 122. The straight segment 121 can slide with the cylinder 211 along the length direction of the straight segment 121. The length direction of the straight segment 121 is, for example, perpendicular to the thickness direction of the mounting bracket 100. Specifically, for example, Figure 5 The direction indicated by arrow C is such that a portion of the cylinder 211 fits into the arc-shaped segment 122. (Reference) Figure 5 As shown, in this layout, the mounting hole 120 is roughly U-shaped.

[0060] In this embodiment, the straight segment 121 can slide and engage with the cylinder 211 along the length of the straight segment 121. This allows the straight segment 121 to provide guidance for the installation of the first base 210, thereby reducing the installation difficulty and improving the installation accuracy of the first base 210. Furthermore, in this embodiment, a portion of the cylinder 211 is in contact with the arc-shaped segment 122, which gives the cylinder 211 a larger mating area with the mounting bracket 100, resulting in better installation reliability of the first base 210.

[0061] In actual use, a portion of the cylinder 211 is slid into the arc-shaped section 122 along the length of the straight section 121. When the cylinder 211 and the arc-shaped section 122 are in contact, it indicates that the first base 210 is installed in place.

[0062] In other alternative embodiments, the mounting hole 120 may not include the straight segment 121 and the arc segment 122. In other words, the mounting hole 120 may be of other shapes. In this case, there is no sliding fit between the mounting hole 120 and the cylinder 211, and the hole wall of the mounting hole 120 may have a gap with the side wall of the cylinder 211, that is, the two do not directly contact each other.

[0063] In a further embodiment, reference is made to... Figure 5 As shown, the hydrogen flame ionization detector also includes a first threaded connector 510, and the annular mating part 212 is detachably connected to the mounting bracket 100 through the first threaded connector 510, which is, for example, a screw.

[0064] Using the solution in this embodiment, the first threaded connector 510 can be disassembled and assembled by rotating it with a screwdriver, thereby enabling the connection or separation of the first base 210 from the mounting bracket 100. When disassembling and assembling other components of the hydrogen flame ionization detector, the use of a screwdriver is often unavoidable. Therefore, there is no need to equip the first base 210 with a special tool, thus reducing costs and simplifying tool management.

[0065] In other embodiments, the hydrogen flame ionization detector may not include the first threaded connector 510. In this case, the hydrogen flame ionization detector may include, for example, a first locking member. The first locking member is sleeved on the first base 210 and threadedly connected to the first base 210. The first locking member is located on the side of the mounting bracket 100 opposite to the annular mating portion 212 and contacts the mounting bracket 100 to clamp a portion of the mounting bracket 100 between the first locking member and the annular mating portion 212, thereby achieving the connection between the first base 210 and the mounting bracket 100. Specifically, the first locking member may be, for example, a nut. In this configuration, for example, a special wrench is required to rotate the first locking member in order to install the first base 210 onto the mounting bracket 100.

[0066] In one alternative embodiment, reference is made to... Figure 1As shown, the hydrogen flame ionization detector includes, for example, a second housing 820. The heating mechanism 700 mentioned above is located in the inner cavity of the second housing 820, and the annular mating part 212 is detachably connected to the mounting bracket 100, for example, via a first threaded connector 510. In this arrangement, when the annular mating part 212 is connected to the mounting bracket 100 via the first threaded connector 510, the rotation of the first threaded connector 510 has virtually no effect on the position of the annular mating part 212, thus eliminating the need for additional fixing of the first base 210, which simplifies the installation process of the first base 210.

[0067] In related technologies, in order to prevent the annular mating part 212 from rotating during installation, for example, it is necessary to connect the heating mechanism 700 to the second housing 820. In this embodiment, the position of the annular mating part 212 remains basically unchanged, so it is not necessary to connect the heating mechanism 700 to the second housing 820. That is to say, in this embodiment, there is no connection relationship between the heating mechanism 700 and the second housing 820.

[0068] In a further embodiment, reference is made to... Figures 1 to 3 As shown, the hydrogen flame ionization detector also includes a housing 600, which is fitted over a portion of the second base 310. The portion of the second base 310 located within the housing 600 has a limiting step 3113. The housing 600 and the limiting step 3113 are in a limiting engagement in the direction from the second reference plane 2122 to the second positioning surface 3111. Specifically, this direction is, for example, [missing information]. Figure 1 The direction indicated by arrow D in the diagram. The housing 600 is connected to the mounting bracket 100, with one end of the housing 600 facing the mounting bracket 100, and has an adjustment gap between it and the mounting bracket 100. Specifically, Figure 2 The dimension line d in the diagram indicates the size of the adjustment gap.

[0069] In this embodiment, the second base 310 is indirectly connected to the mounting bracket 100 via a cover 600. The cover 600 presses the second positioning surface 3111 of the second base 310 against the second reference surface 2122 of the first base 210, thereby bringing the second positioning surface 3111 and the second reference surface 2122 into contact. An adjustment gap is maintained between the cover 600 and the mounting bracket 100. This design provides error compensation space for the machining of the second positioning surface 3111 and the second reference surface 2122. Even if machining errors exist in the second positioning surface 3111 and the second reference surface 2122, the size of the adjustment gap can be flexibly adjusted to bring the second positioning surface 3111 and the second reference surface 2122 into contact. This layout reduces the requirements for the machining accuracy of the second positioning surface 3111 and the second reference surface 2122, simplifying the machining process.

[0070] Optionally, the cover 600 is connected to the mounting bracket 100, for example, via a second threaded connector. In actual use, the position of the cover 600 is changed by rotating the second threaded connector, thereby changing the size of the adjustment gap. The second threaded connector is, for example, a screw.

[0071] Specifically, the hydrogen flame ionization detector also includes, for example, a first housing 810, a mounting bracket 100 connected to the first housing 810, and a portion of the cover 600 located, for example, inside the first housing 810.

[0072] In other embodiments, there may be no adjustment gap between the cover 600 and the mounting bracket 100, in which case the two opposite sides of the cover 600 and the mounting bracket 100 may be in contact.

[0073] In a further embodiment, reference is made to... Figure 2 As shown, the inner wall of the housing 600 is provided with a first clearance groove 610, which extends in a direction away from the center line of the collecting electrode 320. A portion of the annular mating part 212 is located in the first clearance groove 610, and the side of the annular mating part 212 facing away from the mounting bracket 100 is provided with a second clearance groove 2124 extending in the direction of the center line of the collecting electrode 320, so as to leave adjustment space between the side wall of the annular mating part 212 and the first clearance groove 610.

[0074] In this embodiment, a portion of the annular mating part 212 is located in the first clearance groove 610, which increases the mating area between the annular mating part 212 and the mounting bracket 100, thereby improving the stability of the first base 210.

[0075] In actual use, when the size of the adjustment gap mentioned above changes, the size of the adjustment space in this embodiment changes accordingly. The existence of the adjustment space provides clearance for the movement of the cover 600, thereby making the size of the adjustment gap flexible and adjustable.

[0076] In other alternative embodiments, the inner wall of the cover 600 may not have the first clearance groove 610, and the annular mating part 212 may not have the second clearance groove 2124. In this case, the annular mating part 212 may be located entirely in the inner cavity of the cover 600.

[0077] In one alternative embodiment, reference is made to... Figure 1As shown, the hydrogen flame ionization detector also includes, for example, a second locking member 520. The second locking member 520 is sleeved on the second base 310 and threadedly connected to the second base 310. The second locking member 520 is located on the side of the cover 600 away from the mounting bracket 100 and is in contact with the cover 600. With this configuration, the second locking member 520 can restrict the cover 600 from moving away from the mounting bracket 100, thereby allowing the cover 600 to be stably pressed against the limiting step 3113 of the second base 310, thus improving the stability of the cover 600 and the second base 310.

[0078] As one specific implementation method, refer to Figure 1 and Figure 2 As shown, the collecting electrode 320 includes, for example, a cylindrical body 321. One end of the cylindrical body 321 is disposed opposite to the nozzle 220, and this end is, for example, the collecting end of the collecting electrode 320. The cylindrical body 321 is provided with a protrusion 322, which extends in a direction away from the axis of the cylindrical body 321. Optionally, the protrusion 322 protrudes from the cylindrical body 321 radially, for example, and the protrusion 322 is disposed around the cylindrical body 321. The ion collection assembly also includes a first insulator 330 and a second insulator 340. The first insulator 330 and the second insulator 340 are both sleeved on the protrusion 322 and are located on opposite sides of the protrusion 322 in the axial direction of the cylindrical body 321. The protrusion 322, the first insulator 330 and the second insulator 340 are all located in the mounting cavity 3112 of the second seat 310. The first insulator 330 and the second insulator 340 are used to separate the protrusion 322 from the cavity wall of the mounting cavity 3112 to prevent the collecting electrode 320 from making conductive contact with the second seat 310.

[0079] In this embodiment, the distance L between the collecting electrode 320 and the nozzle 220 satisfies, for example, the following relationship:

[0080] Equation 1: L = La - Lb - Lc - Ld + Le;

[0081] For ease of description, the side of the nozzle 220 facing the collecting electrode 320 is defined as the first end face 3211, and the side of the cylindrical body 321 facing the nozzle 220 is defined as the second end face 221. In the above formula, La is the distance between the first end face 3211 of the nozzle 220 and the preset position of the nozzle 220. The selection of the preset position depends on the actual situation. Specifically, the preset position is defined as the first position, Lb is the distance between the first position of the nozzle 220 and the second reference surface 2122 of the first seat 210, Lc is the thickness of the portion of the second seat 310 located between the second insulator 340 and the second reference surface 2122, Ld is the thickness of the second insulator 340, and Le is the distance between the second end face 221 of the cylindrical body 321 and the side of the second insulator 340 facing the protrusion 322. It should be noted that the distances mentioned here refer to the axial distances of the cylindrical body 321, and the thickness directions of the second insulator 340, the second seat 310, and the nozzle 220 are all the same as the axial direction of the cylindrical body 321. Obviously, the dimensions of the mounting bracket 100 are not involved in the above formula. Therefore, the hydrogen flame ionization detector provided in this embodiment eliminates the interference of the dimensions of the mounting bracket 100 on the relative positions of the nozzle 220 and the collecting electrode 320.

[0082] This application also provides a gas chromatograph, which includes the hydrogen flame ionization detector described above, and has the same beneficial effects as the hydrogen flame ionization detector described above, which will not be repeated here.

[0083] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A hydrogen flame ionization detector characterized by, include: Mounting bracket (100) has a first reference surface (110); An air intake assembly includes a first base (210) and a nozzle (220). The first base (210) is connected to the mounting bracket (100), and the nozzle (220) is mounted on the first base (210). The first base (210) has a first positioning surface (2121) facing the first reference surface (110) and a second reference surface (2122) facing away from the first reference surface (110). The first positioning surface (2121) is in contact with the first reference surface (110), and the extension direction of the nozzle (220) intersects with the first positioning surface (2121). An ion collection assembly includes a second seat (310) and a collecting electrode (320). The second seat (310) is connected to the mounting bracket (100). The collecting electrode (320) is mounted on the second seat (310). The second seat (310) has a second positioning surface (3111) that contacts a second reference surface (2122). The extending direction of the collecting electrode (320) intersects with the second positioning surface (3111), and the collecting electrode (320) is disposed opposite to the nozzle (220).

2. The hydrogen flame ionization detector of claim 1, wherein, The first base (210) includes a cylindrical body (211), the first end of the cylindrical body (211) is disposed facing the second positioning surface (3111), and the first end of the cylindrical body (211) is provided with an annular mating part (212) in the circumferential direction. The first surface of the annular mating part (212) is disposed facing the first reference surface (110), and the second surface of the annular mating part (212) is disposed away from the first reference surface (110). The first positioning surface (2121) includes the first surface, the second reference surface (2122) includes the second surface, and the second end of the cylindrical body (211) passes through the mounting bracket (100) and extends out. At least a portion of the nozzle (220) is located in the inner cavity of the cylindrical body (211).

3. The hydrogen flame ionization detector of claim 2, wherein, The second seat (310) is provided with a mounting cavity (3112), at least a portion of the collecting electrode (320) is located in the mounting cavity (3112), and the mounting cavity (3112) is connected to the inner cavity of the cylinder (211) through the first end of the cylinder (211); The hydrogen flame ionization detector further includes an annular seal (400). One of the second positioning surface (3111) and the second surface is provided with a receiving groove (2123) extending along the centerline of the collecting electrode (320). The annular seal (400) is located in the receiving groove (2123) and is arranged around the first end of the cylinder (211). The annular seal (400) is sealed to both the first seat (210) and the second seat (310). The groove wall of the receiving groove (2123) can prevent the annular seal (400) from moving in a direction away from the centerline of the collecting electrode (320).

4. The hydrogen flame ionization detector of claim 2, wherein, The collecting end of the collecting electrode (320) extends into the inner cavity of the cylinder (211) through the first end of the cylinder, and a portion of the nozzle (220) is located inside the collecting end of the collecting electrode (320).

5. The hydrogen flame ionization detector of claim 2, wherein, The mounting bracket (100) is provided with a mounting hole (120) extending along the thickness direction of the mounting bracket (100). The second end of the cylinder (211) passes through the mounting hole (120), and the mounting hole (120) penetrates the side wall of the mounting bracket (100) in a direction perpendicular to the thickness direction of the mounting bracket (100) to form a mounting opening (1211). The mounting opening (1211) allows a part of the cylinder (211) to enter and exit the mounting hole (120).

6. The hydrogen flame ionization detector of claim 5, wherein, The mounting hole (120) includes a straight segment (121) and an arc segment (122). The mounting port (1211) includes a port at one end of the straight segment (121). The other end of the straight segment (121) is connected to the arc segment (122). The straight segment (121) can slide with the cylinder (211) along the length direction of the straight segment (121), and a part of the cylinder (211) is in contact with the arc segment (122).

7. The hydrogen flame ionization detector of claim 2, wherein, The hydrogen flame ionization detector also includes a first threaded connector (510), and the annular mating part (212) is detachably connected to the mounting bracket (100) through the first threaded connector (510).

8. The hydrogen flame ionization detector of claim 2, wherein, The hydrogen flame ionization detector also includes a housing (600), which is fitted over a portion of the second base (310), and the portion of the second base (310) located inside the housing (600) is provided with a limiting step (3113). The housing (600) and the limiting step (3113) are in upper limit engagement in the direction from the second reference plane (2122) to the second positioning plane (3111). The housing (600) is connected to the mounting bracket (100), and one end of the housing (600) is positioned facing the mounting bracket (100) and has an adjustment gap with the mounting bracket (100).

9. The hydrogen flame ionization detector of claim 8, wherein, The inner wall of the housing (600) is provided with a first clearance groove (610), which extends in a direction away from the center line of the collecting electrode (320). A portion of the annular mating part (212) is located in the first clearance groove (610), and the side of the annular mating part (212) facing away from the mounting bracket (100) is provided with a second clearance groove (2124) extending in a direction along the center line of the collecting electrode (320) so as to leave adjustment space between the side wall of the annular mating part (212) and the first clearance groove (610).

10. A gas chromatograph characterized by, Including the hydrogen flame ionization detector as described in any one of claims 1-9.

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