Multi-channel liquid exchange device of chromatograph-mass spectrometer

Abstract

The invention relates to a multi-channel liquid exchange device of a chromatograph-mass spectrometer, relates to the technical field of the chromatograph-mass spectrometer, and realizes the following effects through cooperation of a transfer channel, a cleaning pipe, an isolation plate, a negative pressure pump and other parts: high-efficiency pollution prevention: in a non-liquid supply state, residual liquid and air are sucked through the negative pressure pump; dripping of liquid hanging on the wall is obviously reduced, and pollution to a switching surface is avoided; accurate channel switching: a liquid flowing path is optimized by the transfer channels distributed in a stepped array, and a rapid switching process and accurate positioning are ensured by combining precise meshing of a driving gear and a rack; flexible cleaning and maintenance are achieved, the series-connection channels are matched with the design of turbulent flow rotary vanes and vibration springs, the channels can be flushed in a centralized or independent mode, the cleaning efficiency is greatly improved, meanwhile, liquid drops are effectively intercepted through filter bags and staggered blocking strips, and secondary pollution is prevented; due to the design of the transfer frame and the flexible connecting pipe, pipeline bending and mechanical abrasion are reduced, the maintenance requirement is lowered, and the stability of long-term operation of the system is improved.

Description

Technical Field

[0001] This application relates to the technical field of chromatography-mass spectrometry coupling technology, and in particular to a multi-channel liquid exchange device for a chromatography-mass spectrometry coupling instrument. Background Art

[0002] A mass spectrometer is an instrument used to separate and detect different isotopes. That is, based on the principle that charged particles can be deflected in an electromagnetic field, the process of detecting substances according to the mass differences of atomic, molecular, or molecular fragment of substances can effectively analyze the constituent elements and components of substances. In actual use, the substances to be measured are often complex mixtures, making the mass spectra obtained by the mass spectrometer complex and difficult to analyze. Therefore, a chromatograph is often coupled with a mass spectrometer. Through liquid chromatography or gas chromatography, the mixture is separated and analyzed, and then the separated substances are introduced into the mass spectrometer for mass spectrometry analysis.

[0003] The existing Chinese patent with the authorized announcement number CN117571897B discloses a liquid chromatography-mass spectrometry coupling instrument and a switching device, which includes a waste liquid barrel and a switching mechanism. The waste liquid barrel is fixedly connected with a waste liquid pipe. The switching mechanism includes a frame body, a valve core, an upper valve body, a lower valve body, a chassis, and a switching member that drives the valve core and the chassis to rotate. The upper valve body is fixedly connected with the frame body, and the lower valve body is rotatably connected with the frame body. The upper valve body is provided with a plurality of feed cavities, which are arranged along the circumferential angle of the upper valve body. The lower valve body is provided with a discharge cavity and a waste liquid cavity. The valve core is provided with a plurality of liquid inlets, liquid outlets, and waste liquid outlets. The liquid inlets are arranged at equal angles and equidistantly along the upper end of the valve core. The liquid outlets and the waste liquid outlets are symmetrically arranged about the vertical axis of the valve core at the lower end of the valve core. A pipeline one is connected between one of the liquid inlets and the liquid outlet, the waste liquid outlet is connected with a waste liquid pipeline, and the remaining liquid inlets are all connected with the waste liquid pipeline. The lower valve body is fixedly connected with the chassis, and the waste liquid pipe is fixedly connected with the chassis. When analyzing the same sample, the separation and analysis process of the liquid chromatograph for the sample generally takes a long time. When the chromatograph and the mass spectrometer are connected in parallel one by one, the actual analysis time of the mass spectrometer is short, and it is often in an idle state and the mass spectrometer keeps working, resulting in a low utilization rate of the mass spectrometer. Therefore, the technical solution adopted in the related art is to couple multiple chromatographs with one mass spectrometer and use the switching mechanism to realize the switching of pipelines, so as to selectively connect the liquid outlet pipes of multiple chromatographs with the liquid inlet pipe of the mass spectrometer.

[0004] The related art described above has the following defects: The general principle of its switching mechanism is that the liquid outlet pipe of the chromatograph and the liquid inlet pipe of the mass spectrometer are both connected to the switching mechanism. There is a rotatable switching surface inside the switching mechanism. When the channels of the two switching surfaces are connected to each other, normal liquid supply is achieved. When the channels of the two switching surfaces are not connected, the corresponding channels can be blocked by the switching surface, thereby realizing the opening and closing control between different pipelines. However, in the actual switching process, liquid residues are likely to remain at the ports of the channels near the switching surface. Therefore, during the rotation of the switching mechanism, the residual liquid is easily coated on the switching surface, which is likely to cause contamination and may affect the accuracy of the final detection results. Therefore, it needs to be improved. Summary of the Invention

[0005] In order to reduce the influence of the residual wall-hanging liquid in the pipeline during the rotation process on the switching surface, the present application provides a multi-channel liquid exchange device for a chromatograph-mass spectrometer.

[0006] The multi-channel liquid exchange device for a chromatograph-mass spectrometer provided by the present application adopts the following technical solutions: A multi-channel liquid exchange device for a chromatograph-mass spectrometer includes a chromatograph liquid outlet pipe connected to a chromatograph, a mass spectrometer liquid inlet pipe connected to a mass spectrometer, and a switching mechanism connected between the chromatograph liquid outlet pipe and the mass spectrometer liquid inlet pipe. The switching mechanism includes a transfer box, a cover plate rotatably connected to the top of the transfer box, and a bottom plate rotatably connected to the bottom of the transfer box. The chromatograph liquid outlet pipe is connected to the cover plate, the mass spectrometer liquid inlet pipe is connected to the bottom plate, the transfer box has a through-going transfer channel, and the transfer channel is connected to the corresponding chromatograph liquid outlet pipe and mass spectrometer liquid inlet pipe; A cleaning pipe is arranged inside the chromatograph liquid outlet pipe. The bottom of the cleaning pipe is connected to an isolation plate for blocking the bottom of the chromatograph liquid outlet pipe through a flexible connecting pipe. A cleaning channel is arranged inside the isolation plate. The flexible connecting pipe is connected to the cleaning channel, and the end of the cleaning channel away from the flexible connecting pipe faces the chromatograph liquid outlet pipe. The top of the cleaning pipe extends out of the chromatograph liquid outlet pipe and is connected to a supplementary air pipe and a liquid supply pipe through a switching valve; A negative pressure pump is arranged on the side of the chromatograph liquid outlet pipe.

[0007] By adopting the above technical solutions, efficient switching between the chromatograph liquid outlet pipe and the mass spectrometer liquid inlet pipe is achieved, and the contamination of the equipment by the wall-hanging liquid during the switching process is effectively reduced. Specifically, the switching mechanism composed of the transfer box, the cover plate, and the bottom plate, in combination with the design of the cleaning pipe, the isolation plate, and the negative pressure pump, can ensure the normal flow of liquid in the liquid supply state, and reduce the dripping of the wall-hanging liquid through negative pressure suction in the non-liquid supply state, improving the accuracy of the detection results and extending the service life of the equipment at the same time.

[0008] The specific switching process is as follows: In the liquid supply state, the chromatographic liquid outlet pipe is coaxially placed with the corresponding transfer channel, and the switching valve and the negative pressure pump are in the closed state. In this state, the isolation plate swings downward under its own gravity and enters the interior of the transfer channel. At this time, the bottom of the chromatographic liquid outlet pipe is in the open state, and normal liquid supply can be achieved. In the non-liquid supply state, the chromatographic liquid outlet pipe rotates relative to the corresponding transfer channel. During this process, the switching valve is adjusted to the state where the air supply pipe is connected to the cleaning pipe, and the negative pressure pump is turned on. During the process that the top wall of the transfer box finally pushes the isolation plate upward until the isolation plate blocks the bottom of the chromatographic liquid outlet pipe, the negative pressure pump maintains the negative pressure state inside the chromatographic liquid outlet pipe, and aspirates the air inside the transfer channel and the air inside the cleaning channel and the cleaning pipe from bottom to top, so as to reduce the dripping of the wall-hanging liquid inside the chromatographic liquid outlet pipe. Before switching to the connection of another chromatographic liquid outlet pipe and the corresponding transfer channel, close the switching valve and the negative pressure pump. When the other chromatographic liquid outlet pipe rotates to be coaxial with the corresponding transfer channel, the liquid supply of the other chromatographic liquid outlet pipe can be realized.

[0009] Preferably, several of the transfer channels are arranged in a stepped manner and each has a liquid inlet end, an intermediate section, and a liquid outlet end that are sequentially connected. The liquid inlet end extends to the top wall of the transfer box, the liquid outlet end extends to the bottom wall of the transfer box, and the intermediate sections of several of the transfer channels are sequentially arranged along the thickness direction of the transfer box and the projection position relationship is arranged in an array with the center of the transfer box as the center of the circle.

[0010] By adopting the above technical solution, the transfer channels are arranged in a stepped manner and are divided into a liquid inlet end, an intermediate section, and a liquid outlet end, so that each channel can be arranged orderly in a limited space, improving the space utilization rate and facilitating the connection of pipelines. The design that the liquid inlet end extends to the top wall of the transfer box and the liquid outlet end extends to the bottom wall of the transfer box ensures the smoothness of the liquid flow path and reduces the possibility of liquid residue. The intermediate sections are sequentially arranged along the thickness direction of the transfer box and the projection positions are distributed in an array with the center of the transfer box as the center of the circle, further optimizing the channel layout, improving the switching accuracy, and reducing the risk of cross-contamination.

[0011] Preferably, several of the transfer channels are connected in series through a series channel, and a series valve is arranged on the series channel.

[0012] By adopting the above technical solution, when it is necessary to centrally flush several transfer channels, the series valve can be opened to connect several transfer channels in an S-shaped series, so that they can be centrally flushed after each of several transfer channels is used once, achieving a more energy-saving effect.

[0013] Preferably, a flow disturbance swirl blade is arranged inside the series channel, and the flow disturbance swirl blade is spiral and arranged parallel to the axial direction of the series channel.

[0014] By adopting the above technical solution, the setting of the spoiler blades can effectively enhance the turbulence degree of the liquid in the series channels. Specifically, when the liquid flows through the series channels, the spiral spoiler blades will guide the liquid to form a rotating flow, thereby increasing the contact area between the liquid and the channel wall, which helps to remove the residual substances in the channels. At the same time, this structural design can also promote more uniform liquid mixing, further improving the flushing efficiency and ensuring the cleaning effect of the transfer channel during the centralized flushing process.

[0015] Preferably, the spoiler blades are connected to the series channels through vibration springs.

[0016] By adopting the above technical solution, the spoiler blades are connected to the series channels through vibration springs, which can generate vibrations during the liquid flushing process, enhance the turbulence effect of the liquid, further improve the cleaning efficiency, and ensure that the residual substances in the transfer channel are completely removed. At the same time, the design of the vibration springs can also effectively prevent the impact force generated during the flushing process from damaging the equipment and extend the service life of the device.

[0017] Preferably, a transfer rack is fixedly arranged between the cover plate and the bottom plate.

[0018] By adopting the above technical solution, the setting of the transfer rack simplifies the operation process of channel switching. When switching channels subsequently, only the transfer box needs to be rotated to complete the channel switching, without separately rotating the cover plate and the bottom plate, thereby avoiding the bending of the chromatographic liquid outlet pipe and the mass spectrometry liquid outlet pipe connected to the cover plate and the bottom plate due to frequent switching, and significantly extending the service life of the pipeline.

[0019] Preferably, a driving gear is rotatably arranged on the transfer rack, a driving rack is arranged on the side wall of the transfer box, the driving gear is meshed with the driving rack, and the transfer rack is also provided with a transfer driving member for driving the driving gear to rotate.

[0020] By adopting the above technical solution, precise rotation control of the transfer box is achieved. Specifically, the cooperation between the driving gear and the driving rack ensures the stability and accuracy of the transfer box during rotation, thereby improving the operation reliability when switching the connection between different chromatographic liquid outlet pipes and the transfer channel. At the same time, the design of the transfer driving member further simplifies the operation process, improves the automation degree of the equipment, reduces the errors that may be brought by human intervention, and ensures good sealing and fast switching ability between channels during the liquid exchange process.

[0021] Preferably, a flushing pipe is connected to the cover plate, and a recovery pipe is connected to the bottom plate.

[0022] By adopting the above technical solution, when a transfer channel needs to be flushed, the transfer box is rotated to connect the corresponding transfer channel with the flushing pipe and the recovery pipe, so that the specific transfer channel can be flushed, and the waste liquid can be collected through the recovery pipe. This design can effectively remove residual substances in the transfer channel and avoid cross contamination, while ensuring that the waste liquid is properly handled, improving the cleaning efficiency and environmental performance of the entire system.

[0023] Preferably, the negative pressure pump is connected to a filter bag, the bottom of the filter bag is open, a plurality of gear bars are arranged inside the filter bag, and the plurality of gear bars are arranged in a staggered manner.

[0024] By adopting the above technical solution, the design of the baffles inside the filter bag can effectively absorb sporadic droplets in the airflow. Specifically, the staggered baffles restrict the gas flow path, so that the airflow mixed with droplets is forced to change direction multiple times when passing through the baffles, thereby increasing the chance of droplets colliding with the baffles. This structure not only avoids the secondary pollution of the external environment caused by the droplets discharged with the airflow, but also improves the cleaning efficiency and stability of the negative pressure system. Among them, the design of the opening at the bottom of the filter bag facilitates the regular cleaning of the adsorbed liquid to ensure the long-term stable operation of the system.

[0025] An exchange method for a multi-channel liquid exchange device based on a chromatography-mass spectrometer, in which, in the liquid supply state, a chromatographic liquid outlet pipe is coaxially placed with a corresponding transfer channel, and a conversion valve and a negative pressure pump are in a closed state, in which the isolation plate swings downward under its own gravity and enters the interior of the transfer channel, and at this time, the bottom of the chromatographic liquid outlet pipe is in an open state, so that liquid can be supplied normally; In the non-liquid supply state, the chromatographic liquid outlet pipe and the corresponding transfer channel rotate relative to each other. During this process, the conversion valve is adjusted to a state where the air supply pipe and the cleaning pipe are connected, and the negative pressure pump is turned on. When the top wall of the transfer box finally pushes the isolation plate upward until the isolation plate blocks the bottom of the chromatographic liquid outlet pipe, the negative pressure pump maintains the negative pressure state inside the chromatographic liquid outlet pipe, and sucks the air inside the transfer channel and the air inside the cleaning channel and the cleaning pipe from bottom to top, thereby reducing the dripping of the wall-hanging liquid in the chromatographic liquid outlet pipe. Before switching to another chromatographic liquid outlet tube to connect with the corresponding transfer channel, close the conversion valve and the negative pressure pump. When the other chromatographic liquid outlet tube rotates to be coaxial with the corresponding transfer channel, the liquid supply of the other chromatographic liquid outlet tube can be realized.

[0026] By adopting the above technical solution, the chromatographic liquid outlet tube can be accurately docked with the transfer channel and normally supply liquid in the liquid supply state, and the dripping of the wall liquid in the chromatographic liquid outlet tube can be effectively reduced in the non-liquid supply state, thereby improving the cleanliness and reliability of the switching process, thereby improving the accuracy of the overall detection results. Specifically: In the liquid supply state, the isolation plate swings downward by its own gravity into the internal transfer channel to ensure that the bottom of the chromatographic liquid outlet pipe is opened to achieve smooth liquid supply.

[0027] In the non-liquid supply state, the switching valve is adjusted to connect the gas supply pipe and the cleaning pipe, and the negative pressure pump is used to maintain the negative pressure state inside the chromatographic liquid outlet pipe, sucking out the air in the transfer channel, cleaning channel and cleaning pipe, significantly reducing the risk of dripping of the wall-hanging liquid.

[0028] During the switching process, the switching valve and the negative pressure pump are closed, and the liquid supply operation is restored after the other chromatographic liquid outlet pipe rotates into place, realizing the efficient and stable multi-channel liquid exchange function.

[0029] In summary, the present application includes at least one of the following beneficial technical effects: 1. In the non-liquid supply state, the air inside the chromatographic liquid outlet pipe and the cleaning channel is extracted by the negative pressure pump, effectively reducing the dripping of the wall-hanging liquid, significantly reducing the pollution of the switching surface by the residual liquid during the switching process, and improving the accuracy of the detection result; 2. The transfer channels are arranged in a stepped manner and distributed in an array, optimizing the pipeline layout, facilitating the simultaneous management and rapid switching of multiple channels, and improving the overall working efficiency; 3. The flushing pipe and the recovery pipe are provided, which can separately flush a specific transfer channel when needed and collect the waste liquid centrally, avoiding secondary pollution, and enhancing the cleanliness and maintenance convenience of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a schematic structural diagram of an embodiment of the present application; Figure 2 is a schematic structural diagram for showing the connection relationship between the transfer box and the transfer driving member in an embodiment of the present application; Figure 3 is a schematic structural diagram for showing the connection relationship between the transfer channel, the mass spectrometry liquid inlet pipe and the chromatographic liquid outlet pipe in an embodiment of the present application; Figure 4 is a schematic structural diagram for showing the positional relationship between the transfer channel and the series channel in an embodiment of the present application; Figure 5 is a schematic structural diagram for showing the connection relationship of the series channel in an embodiment of the present application; Figure 6 is a schematic structural diagram for showing the connection relationship between the flow disturbing rotary blade and the series channel in an embodiment of the present application; Figure 7 is a schematic structural diagram for showing the state where the isolation plate flips downward to open the bottom of the chromatographic liquid outlet pipe in an embodiment of the present application; Figure 8This is a schematic structural diagram in the embodiment of the present application to show the structure when the isolation plate is turned upward to close the bottom of the chromatographic liquid outlet pipe; Figure 9 This is a schematic structural diagram in the embodiment of the present application to show the connection relationship between the cleaning pipe, the connecting pipe and the isolation plate.

[0031] In the figure: 1. Transfer box; 10. Transfer channel; 11. Cover plate; 12. Bottom plate; 13. Transfer rack; 14. Driving gear; 15. Driving rack; 16. Transfer driving part; 17. Flushing pipe; 18. Recovery pipe; 2. Chromatograph; 21. Chromatographic liquid outlet pipe; 22. Cleaning pipe; 23. Connecting pipe; 24. Isolation plate; 240. Cleaning channel; 25. Conversion valve; 26. Supplementary air pipe; 27. Liquid supply pipe; 28. Negative pressure pump; 29. Filter bag; 291. Bar; 3. Mass spectrometer; 31. Mass spectrometry inlet pipe; 4. Series channel; 41. Series valve; 42. Turbulence swirl blade; 43. Vibration spring. Detailed implementation manners

[0032] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings. The described embodiments are only possible technical implementations of the present invention, not all possible implementations. Those skilled in the art can completely combine the embodiments of the present invention to obtain other embodiments without creative labor, and these embodiments are also within the protection scope of the present invention.

[0033] The inventors of the present application found that the mass spectrometer, as a precision analysis device, is widely used in the fields of chemistry, biology, medicine, etc. However, traditional switching devices are prone to cross-contamination caused by residual liquid in the pipeline during the switching process, seriously affecting the reliability of detection data. For example, although the rotary disk design can achieve multi-channel switching, its mechanical contact surface is prone to carry residual liquid to adjacent channels during rotation, resulting in sample contamination. Therefore, the present application mainly adopts a multi-channel liquid exchange device for a chromatograph-mass spectrometer, including components such as a transfer box, a cover plate, a bottom plate, a chromatographic liquid outlet pipe and a mass spectrometry inlet pipe, and related cleaning components, achieving the effects of reducing residual liquid contamination and improving detection accuracy. The following is a further detailed description of the present application. Embodiment

[0034] Refer to Figure 1 And Figure 2, the multi-channel liquid exchange device of the chromatography-mass spectrometry combined instrument provided by the embodiments of the present application includes a transfer box 1, a cover plate 11 rotatably connected to the top of the transfer box 1, and a bottom plate 12 rotatably connected to the bottom of the transfer box 1. The transfer box 1, the cover plate 11 and the bottom plate 12 are connected by bearings, which ensures the rotation flexibility and reduces the wear at the same time. Specifically, a transfer rack 13 in the form of a frame is fixedly arranged between the cover plate 11 and the bottom plate 12. A driving gear 14 is arranged on the side of the transfer rack 13. A driving rack 15 made of metal is welded on the side wall of the transfer box 1. The driving gear 14 is in close meshing with the driving rack 15. The transfer rack 13 is also provided with a stepping motor as a transfer driving member 16 for driving the driving gear 14 to rotate. By controlling the stepping motor, the transfer box 1 can be driven to accurately rotate relative to the cover plate 11 and the bottom plate 12, so as to automatically and quickly complete the selection and switching process of the required channels.

[0035] Refer to Figure 1 and Figure 2 , the cover plate 11 is connected with a plurality of chromatographic liquid outlet pipes 21 and a flushing pipe 17. The top of the chromatographic liquid outlet pipe 21 is connected to the chromatograph 2 for receiving the liquid processed by the chromatograph 2, and the top of the flushing pipe 17 is connected to the cleaning liquid. The bottom plate 12 is connected with a plurality of mass spectrometry liquid inlet pipes 31 and a recovery pipe 18. The mass spectrometry liquid inlet pipe 31 is used to transport the liquid processed by the chromatograph 2 into the mass spectrometer 3 for analysis, and the recovery pipe 18 is used to collect the waste liquid after flushing. The specific connection mode between a plurality of pipe ends and the cover plate 11 or the bottom plate 12 can be installed by means of quick-release joints, which is convenient for later maintenance.

[0036] Refer to Figure 3 and Figure 4 , the inside of the transfer box 1 has a plurality of transfer channels 10 arranged through. When the transfer box 1 rotates to a specific angle, the two ends of the transfer channel 10 are respectively communicated with the corresponding chromatographic liquid outlet pipe 21 and the mass spectrometry liquid inlet pipe 31, or the two ends of the transfer channel 10 are respectively communicated with the flushing pipe 17 and the recovery pipe 18, or the two ends of the transfer channel 10 are respectively closed by the cover plate 11 and the bottom plate 12.

[0037] A number of transfer channels 10 are all arranged in a stepped manner, distributed in a Z shape, and have two turning points. Therefore, a number of transfer channels 10 all form a liquid inlet end, an intermediate section, and a liquid outlet end that are connected in sequence. The liquid inlet end extends to the top wall of the transfer box 1 and is sealed and docked with a conical sealing ring. The liquid outlet end extends to the bottom wall of the transfer box 1 and is also installed and sealed with a conical sealing ring of the same specification. The intermediate sections of a number of transfer channels 10 are arranged in sequence along the thickness direction of the transfer box 1, and the projection positional relationship is distributed in an array with the center of the transfer box 1 as the center of the circle. In addition, a number of transfer channels 10 are connected in series through a series channel 4, and an electrically controlled series valve 41 is installed on the series channel 4. When it is necessary to collectively flush a number of transfer channels 10, all series valves 41 are opened to establish an S-shaped water flow path to achieve efficient flushing.

[0038] Refer to Figure 5 and Figure 6 , a turbulence-rotating blade 42 is configured inside the series channel 4. The turbulence-rotating blade 42 is spiral and arranged parallel to the axis of the series channel 4, and the turbulence-rotating blade 42 is connected to the series channel 4 through a vibration spring 43 made of high-strength stainless steel to ensure stable operation under long-term vibration conditions. This structure significantly enhances the flushing strength and thoroughly cleans the residual liquid. In this embodiment, two series valves 41 are provided for each section of the transfer channel 10, and the two series valves 41 are respectively located on both sides of the turbulence-rotating blade 42. Under normal conditions, both ends of the series channel 4 are adjusted to a closed state through the series valves 41 to prevent the series channel 4 from communicating with the inside of the transfer channel 10 during normal liquid supply, causing sample contamination.

[0039] Refer to Figure 7 , Figure 8 and Figure 9 , a cleaning pipe 22 is connected from the side wall of the chromatographic liquid outlet pipe 21. A part of the cleaning pipe 22 extends into the chromatographic liquid outlet pipe 21, and the bottom of the cleaning pipe 22 extends to the bottom of the chromatographic liquid outlet pipe 21. The bottom of the cleaning pipe 22 is connected to a partition plate 24 through a flexible connecting pipe 23 made of silica gel, and the partition plate 24 itself is also made of an elastic material. When the chromatographic liquid outlet pipe 21 is connected to the transfer channel 10, the partition plate 24 can naturally fall into the transfer channel 10. At this time, the chromatographic liquid outlet pipe 21 and the transfer channel 10 are in a connected state. When rotation causes the chromatographic liquid outlet pipe 21 and the transfer channel 10 to gradually deviate, the abutting surface will push the partition plate 24 to turn upward until it returns to the inside of the chromatographic liquid outlet pipe 21 and seals the bottom of the chromatographic liquid outlet pipe 21.

[0040] The interior of the partition plate 24 is also provided with a cleaning channel 240. The flexible connecting pipe 23 is communicated with the cleaning channel 240, and one end of the cleaning channel 240 away from the flexible connecting pipe 23 is arranged towards the chromatographic liquid outlet pipe 21. The top of the cleaning pipe 22 extends out from the side wall of the chromatographic liquid outlet pipe 21 and is communicated with a gas supply pipe 26 and a liquid supply pipe 27 through a conversion valve 25 fixed by a threaded joint. The conversion valve 25 is a three-way valve, and two states of air supply or liquid supply can be selected by adjusting the conversion valve 25. In addition, a negative pressure pump 28 of the vacuum pump type is arranged on the side of the chromatographic liquid outlet pipe 21. The negative pressure pump 28 can maintain the negative pressure state inside the chromatographic liquid outlet pipe 21 in the non-liquid supply state of the chromatographic liquid outlet pipe 21, and cooperate with the gas supply pipe 26 to pump the air at the bottom of the chromatographic liquid outlet pipe 21 from bottom to top to the negative pressure pump 28 and discharge it from the chromatographic liquid outlet pipe 21. In this process, the wall-hanging liquid can be better removed or the secondary pollution caused by the dripping of the wall-hanging liquid can be reduced. When the bottom of the chromatographic liquid outlet pipe 21 is closed, the negative pressure pump 28 can also be turned off, and the conversion valve 25 can be adjusted to the liquid supply state. In this state, the chromatographic liquid outlet pipe 21 can be internally cleaned by using the liquid supply pipe 27.

[0041] In addition, the outlet of the negative pressure pump 28 is connected with a filter bag 29. The bottom opening of the filter bag 29 is beneficial to exhaust. A plurality of layers of staggered baffles 291 are arranged inside the filter bag 29. The baffles 291 are made of a fiber material with a certain water absorption capacity. The liquid-containing gas entering the filter bag 29 will be forced to change the flow direction and impact the surface of the baffles 291 multiple times, and finally most of the tiny liquid droplets can be effectively intercepted and captured, avoiding secondary pollution to the surrounding air.

[0042] The implementation principle of this embodiment is as follows: By introducing a cleaning assembly composed of the cleaning pipe 22, the flexible connecting pipe 23, and the partition plate 24, the effective cleaning of the interior of the chromatographic liquid outlet pipe 21 is realized, and the pollution risk caused by the wall-hanging liquid to the switching surface is reduced. Especially in the non-liquid supply state, with the action of the negative pressure pump 28, a stable negative pressure environment is formed, further improving the cleaning effect. Compared with the traditional single mechanical closing method, this design scheme takes into account both functionality and reliability, greatly improving the operation stability of the equipment. The newly added transfer rack 13 and its drive system optimize the overall structure, not only simplifying the switching process but also improving the automation degree. Various auxiliary facilities such as the series channel 4, the turbulent flow rotary blade 42, the vibration spring 43, and the filter bag 29 work together to comprehensively ensure the cleanliness level of the system, ensuring that the best performance can be obtained for each switching.

[0043] The beneficial effects of this embodiment are further reflected in: The stepped layout of the transfer channel 10: By arranging the middle section of the transfer channel 10 in sequence along the thickness direction of the transfer box 1 and distributing it in an array around the center, the space utilization rate is optimized.

[0044] The synergistic effect of the flexible connecting tube 23 and the isolation plate 24: The flexible silicone connecting tube 23 has both corrosion resistance and elasticity, and can adjust its angle adaptively under the gravity of the isolation plate 24 to ensure sealing. The guiding design of the cleaning channel 240 inside the isolation plate 24 allows the airflow to flush the wall of the chromatographic liquid outlet tube 21 in a directional manner, further reducing the attachment of residual liquid.

[0045] Enhanced cleaning of the turbulent vanes 42 and the vibration springs 43: The spiral turbulent vanes 42 generate eddies when the liquid flows through, and combined with the high-frequency vibration of the vibration springs 43, the turbulent intensity of the liquid is enhanced, effectively stripping off the deposits on the channel wall. This design is particularly suitable for high-viscosity liquid cleaning scenarios.

[0046] The droplet interception effect of the filter bag 29 and the baffle 291: the multi-layer staggered baffles 291 in the filter bag 29 force the liquid-containing airflow to turn multiple times, and the droplet collision interception rate is higher. The bottom opening design is convenient for regular cleaning or drying to prevent the filter bag 29 from being too wet, ensuring the long-term stable operation of the negative pressure system.

[0047] This application achieves the following core advantages through the comprehensive application of the above technical solutions: Cross-contamination control: The combination of negative pressure suction and directional cleaning technology reduces the risk of residual liquid contamination during the switching process, ensuring the purity and accuracy of the test data; Convenient operation: The introduction of the transfer rack 13 and the automated drive system simplifies the channel switching process, which is especially suitable for high-throughput detection scenarios; Energy saving and environmental protection: The centralized flushing mode of the series channel 4 saves the amount of cleaning liquid compared with the traditional channel-by-channel cleaning. Combined with the design of the waste liquid recovery pipe 18, it further reduces resource waste and environmental burden; Improved durability: The low-wear design of the transfer box 1 and the pipeline extends the life of key components such as the pipeline, significantly reducing the cost of the entire life cycle of the equipment.

[0048] The embodiment of the present application also discloses a multi-channel liquid exchange method for a chromatography-mass spectrometer, and an exchange method based on a multi-channel liquid exchange device for a chromatography-mass spectrometer. In the liquid supply state, the chromatographic liquid outlet pipe 21 is coaxially placed with the corresponding transfer channel 10, and the conversion valve 25 and the negative pressure pump 28 are in a closed state. In this state, the isolation plate 24 swings downward under its own gravity and enters the interior of the transfer channel 10. At this time, the bottom of the chromatographic liquid outlet pipe 21 is in an open state, and liquid can be supplied normally. In the non-liquid supply state, the chromatographic liquid outlet pipe 21 rotates relative to the corresponding transfer channel 10. During this process, the switching valve 25 is adjusted to a state where the air supply pipe 26 is connected to the cleaning pipe 22, and the negative pressure pump 28 is turned on. When the top wall of the transfer box 1 finally pushes the isolation plate 24 upward until the isolation plate 24 blocks the bottom of the chromatographic liquid outlet pipe 21, the negative pressure pump 28 maintains the negative pressure state inside the chromatographic liquid outlet pipe 21, sucking the air inside the transfer channel 10, as well as the air inside the cleaning channel 240 and the cleaning pipe 22 from bottom to top, thereby reducing the dripping of the wall-hanging liquid inside the chromatographic liquid outlet pipe 21; Before switching to the connection between another chromatographic liquid outlet pipe 21 and the corresponding transfer channel 10, the switching valve 25 and the negative pressure pump 28 are closed. When another chromatographic liquid outlet pipe 21 rotates to be coaxial with the corresponding transfer channel 10, the liquid supply to another chromatographic liquid outlet pipe 21 can be realized.

[0049] By adopting the above technical solutions, it is possible to ensure the accurate docking and normal liquid supply between the chromatographic liquid outlet pipe 21 and the transfer channel 10 in the liquid supply state, and at the same time effectively reduce the dripping of the wall-hanging liquid inside the chromatographic liquid outlet pipe 21 in the non-liquid supply state, improving the cleanliness and reliability during the switching process, thereby enhancing the accuracy of the overall detection results.

[0050] Specifically: In the liquid supply state, the isolation plate 24 swings downward by its own gravity and enters the inside of the transfer channel 10 to ensure that the bottom of the chromatographic liquid outlet pipe 21 is opened to achieve smooth liquid supply.

[0051] In the non-liquid supply state, the switching valve 25 is adjusted to connect the air supply pipe 26 with the cleaning pipe 22, and by means of the negative pressure pump 28, the negative pressure state inside the chromatographic liquid outlet pipe 21 is maintained, sucking out the air inside the transfer channel 10, the cleaning channel 240 and the cleaning pipe 22, significantly reducing the risk of dripping of the wall-hanging liquid.

[0052] During the switching process, the switching valve 25 and the negative pressure pump 28 are closed, and after another chromatographic liquid outlet pipe 21 rotates in place, the liquid supply operation is restored, realizing the efficient and stable multi-channel liquid exchange function.

[0053] The above are all the preferred embodiments of the present application, and the protection scope of the present application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A multi-channel liquid exchange device for a gas chromatography-mass spectrometry instrument, comprising a chromatographic outlet pipe (21) connected to a chromatograph (2), a mass spectrometry inlet pipe (31) connected to a mass spectrometer (3), and a switching mechanism connected between the chromatographic outlet pipe (21) and the mass spectrometry inlet pipe (31), characterized in that: The switching mechanism includes a transfer box (1), a cover plate (11) rotatably connected to the top of the transfer box (1), and a bottom plate (12) rotatably connected to the bottom of the transfer box (1). The chromatographic liquid outlet pipe (21) is connected to the cover plate (11), and the mass spectrometry liquid inlet pipe (31) is connected to the bottom plate (12). The transfer box (1) has a transfer channel (10) arranged through it, and the transfer channel (10) is connected and communicated with the corresponding chromatographic liquid outlet pipe (21) and mass spectrometry liquid inlet pipe (31). A cleaning pipe (22) is arranged inside the chromatographic liquid outlet pipe (21). The bottom of the cleaning pipe (22) is connected with a partition plate (24) for blocking the bottom of the chromatographic liquid outlet pipe (21) through a flexible connecting pipe (23). A cleaning channel (240) is arranged inside the partition plate (24). The flexible connecting pipe (23) is connected and communicated with the cleaning channel (240), and one end of the cleaning channel (240) away from the flexible connecting pipe (23) is arranged towards the chromatographic liquid outlet pipe (21). The top of the cleaning pipe (22) extends out of the chromatographic liquid outlet pipe (21) and is connected and communicated with a gas supply pipe (26) and a liquid supply pipe (27) through a switching valve (25). A negative pressure pump (28) is arranged on the side of the chromatographic liquid outlet pipe (21).

2. The multi-channel liquid exchange device of a gas chromatography-mass spectrometry instrument according to claim 1, characterized in that: A plurality of the transfer channels (10) are arranged in a stepped manner and each has a liquid inlet end, an intermediate section, and a liquid outlet end that are sequentially connected and communicated. The liquid inlet end extends to the top wall of the transfer box (1), and the liquid outlet end extends to the bottom wall of the transfer box (1). The intermediate sections of the plurality of transfer channels (10) are sequentially arranged along the thickness direction of the transfer box (1), and their projection positional relationships are arranged in an array with the center of the transfer box (1) as the center of the circle.

3. The multi-channel liquid exchange device of a gas chromatography-mass spectrometry instrument according to claim 2, characterized in that: A plurality of the transfer channels (10) are connected in series through a series channel (4), and the series channel (4) is provided with a series valve (41).

4. The multi-channel liquid exchange device of a gas chromatography-mass spectrometry instrument according to claim 3, wherein: A flow disturbing spiral blade (42) is arranged inside the series channel (4). The flow disturbing spiral blade (42) is spiral and arranged parallel to the axial direction of the series channel (4).

5. The multi-channel liquid exchange device of a gas chromatography-mass spectrometry instrument according to claim 4, wherein: The flow disturbing spiral blade (42) is connected to the series channel (4) through a vibration spring (43).

6. The multi-channel liquid exchange device of a gas chromatography-mass spectrometry instrument according to claim 1, characterized in that: A transfer frame (13) is fixedly arranged between the cover plate (11) and the bottom plate (12).

7. The multi-channel liquid exchange device of a gas chromatography-mass spectrometry instrument according to claim 6, wherein: A driving gear (14) is rotatably arranged on the transfer frame (13). A driving rack (15) is arranged on the side wall of the transfer box (1). The driving gear (14) meshes with the driving rack (15), and the transfer frame (13) is further provided with a transfer driving member (16) for driving the driving gear (14) to rotate.

8. The multi-channel liquid exchange device of a gas chromatography-mass spectrometry instrument according to claim 1, wherein: The cover plate (11) is connected with a flushing pipe (17), and the bottom plate (12) is connected with a recovery pipe (18).

9. The multi-channel liquid exchange device of a gas chromatography-mass spectrometry instrument according to claim 1, characterized in that: The negative pressure pump (28) is connected with a filter bag (29). The bottom of the filter bag (29) is open, and a plurality of baffle strips (291) are arranged inside the filter bag (29). The plurality of baffle strips (291) are arranged in a staggered manner.

10. A switching method for a multi-channel liquid exchange device of a gas chromatography-mass spectrometry instrument according to any one of claims 1-9, characterized in that: In the liquid supply state, the chromatographic liquid outlet pipe (21) is coaxially placed with the corresponding transfer channel (10), and the switching valve (25) and the negative pressure pump (28) are in the closed state. In this state, the isolation plate (24) swings downward under its own gravity and enters the inside of the transfer channel (10). At this time, the bottom of the chromatographic liquid outlet pipe (21) is in the open state, and normal liquid supply can be achieved; In the non-liquid supply state, the chromatographic liquid outlet pipe (21) rotates relative to the corresponding transfer channel (10). During this process, the switching valve (25) is adjusted to the state where the air supply pipe (26) is connected to the cleaning pipe (22), and the negative pressure pump (28) is turned on. During the process that the top wall of the transfer box (1) finally pushes the isolation plate (24) upward until the isolation plate (24) blocks the bottom of the chromatographic liquid outlet pipe (21), the negative pressure pump (28) maintains the negative pressure state inside the chromatographic liquid outlet pipe (21), and sucks the air inside the transfer channel (10) and the air inside the cleaning channel (240) and the cleaning pipe (22) from bottom to top, so as to reduce the dripping of the wall-hanging liquid inside the chromatographic liquid outlet pipe (21); Before switching to the connection between another chromatographic liquid outlet pipe (21) and the corresponding transfer channel (10), the switching valve (25) and the negative pressure pump (28) are closed. When another chromatographic liquid outlet pipe (21) rotates to be coaxial with the corresponding transfer channel (10), the liquid supply of another chromatographic liquid outlet pipe (21) can be realized.

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