A pre-treatment sample traction type liquid addition sampling system

Abstract

The present invention discloses a magnetic traction sampling device for pre-treatment samples, including a slider, a guide rail, a piston, a first magnet, a second magnet, a fixed seat, a sampling needle and an air source assembly. The guide rail is vertically installed on the fixed seat, a piston cavity is arranged inside the guide rail, the piston is sealed and fitted in the piston cavity, a first magnet is fixed on the piston, the slider is fitted on the guide rail and slides axially along the guide rail, the sampling needle is installed on the slider, a second magnet is fixed on the slider, and the magnetic properties of the second magnet are opposite to those of the first magnet; a gas passage is arranged inside the fixed seat, the gas passage is connected with the piston cavity to form an airtight chamber, an air port is provided in the gas passage, and an air source assembly is connected to the air port to enter and exit pressurized gas into and out of the airtight chamber, thereby driving the piston to move up and down, and then driving the slider and the sampling needle to feed up and down. This case also discloses a magnetic traction sampling system for pre-treatment samples, which is based on flexible design and fully sealed design, can be flexibly arranged according to space, has a small size, no consumables, is safer and more stable to use, and has high corrosion resistance.

Description

Technical Field

[0001] The invention relates to the technical field of pre-processing instruments, and in particular to a pre-processing sample magnetic traction sampling device and system. Background Art

[0002] The existing prior document CN201120411274 discloses a sampling needle motion device guided by a flexible shaft driven sliding guide rail. The device adopts a sampling motion guided by a flexible shaft driven sliding guide rail, wherein one end of the flexible shaft is fixed on a fixed block, and the other end is fixed on a turntable. The turntable rotates to drive the flexible shaft to reciprocate and pull the fixed block, thereby realizing the liquid addition and waste discharge of the sampling needle. However, this scheme has high requirements for the host space. In order to achieve the minimum curvature bending radius of the flexible shaft, sufficient space needs to be left in the Z-axis direction. Therefore, the host structure is relatively large, and the flexible shaft will be damaged due to frequent bending and friction, and consumables need to be replaced regularly.

[0003] In addition, the automatic sampler disclosed in the prior document CN201210202748 adopts a traditional mechanical three-axis transmission design, which has the following disadvantages: first, the Z-axis adopts a guide rail plus a synchronous belt drive, which makes the Z-axis structure complex and heavy, and increases the load on the Y-axis movement; second, the Z-axis adopts a synchronous belt structure, which cannot be fully sealed and has poor corrosion resistance; third, due to the rigid design, there is a problem of the injection needle being bent and damaged due to positioning during the Z-axis descending process.

[0004] In view of the above, this case arises. Summary of the invention

[0005] The purpose of the present invention is to provide a pre-treatment sample traction type liquid addition sampling system, which is based on a flexible design and can be flexibly arranged according to space. It has a small size, no consumables, is safer and more stable to use, and the entire system is fully sealed and highly corrosion-resistant.

[0006] To achieve the above-mentioned purpose, the solution of the present invention is: a pre-processed sample magnetic traction sampling device, comprising a slider, a guide rail, a piston, a first magnet, a second magnet, a fixing seat, a sampling needle and a gas source assembly;

[0007] The guide rail is vertically mounted on the fixed seat, a piston cavity is arranged in the guide rail, the piston is sealed and fitted in the piston cavity, the first magnet is fixed on the piston, the slider is fitted on the guide rail and slides axially along the guide rail, the sampling needle is mounted on the slider, the second magnet is fixed on the slider, and the magnetic properties of the second magnet are opposite to those of the first magnet;

[0008] A gas passage is provided in the fixing seat, the gas passage is connected with the piston cavity to form an airtight chamber, a gas port is provided in the gas passage, and the gas source assembly is connected to the gas port to introduce or discharge pressurized gas into the airtight chamber, thereby driving the piston to move up and down, and further driving the slider and the sampling needle to feed up and down.

[0009] Preferably, the sampling device also includes a third magnet and a magnetic induction module, the third magnet is fixed at the bottom of the slider, the magnetic induction module is installed on a fixed seat directly below the third magnet, the magnetic induction module is connected to the air source assembly, and a magnetic induction contact is provided on the magnetic induction module. When the slider moves down to the point where the third magnet contacts the magnetic induction contact, the magnetic induction module sends an intake signal to the air source assembly, the air source assembly receives the intake signal and starts to pass pressurized gas into the airtight chamber, the pressurized gas squeezes the piston upward, drives the slider and the sampling needle to stop moving downward, and starts to feed upward.

[0010] Preferably, the fixing seat is also provided with a magnetic induction avoidance groove for placing the magnetic induction module.

[0011] Preferably, the air source assembly comprises an air source three-way solenoid valve, an air inlet pump and an air outlet pump, and the three valve ports of the air source three-way solenoid valve are respectively connected to the air inlet pump, the air outlet pump and the air port through hoses.

[0012] Preferably, the sliding block is provided with a mounting hole for the sampling needle to penetrate and fit into.

[0013] Preferably, an upper limit block is provided on the top of the guide rail, and the upper limit block is provided with a piston cavity exhaust hole.

[0014] Preferably, the fixed seat comprises a fixed upper seat, a fixed lower seat and a fastener, and the fixed upper seat is sealed and fixed above the fixed lower seat by the fastener.

[0015] A pre-treatment sample magnetic traction sampling system, comprising the above-mentioned pre-treatment sample magnetic traction sampling device, a liquid adding component, a liquid adding needle, a sample tube, a peristaltic pump, a detector and a waste liquid bottle;

[0016] The fixing seat is provided with a liquid adding channel, one end of the liquid adding channel is connected to the liquid adding component through a hose, and the other end of the liquid adding channel is connected to the liquid adding needle, so that the liquid adding component adds liquid to the liquid adding needle through the liquid adding channel, the liquid adding needle and the sampling needle are inserted into the sample tube together, the sampling needle is connected to the liquid extraction port of the peristaltic pump through a hose, the liquid discharge port of the peristaltic pump is connected to the inlet of the detector through a hose, and the outlet of the detector is connected to the waste liquid bottle through a hose.

[0017] Preferably, the liquid adding assembly is composed of a liquid adding three-way solenoid valve, a sample bottle and a syringe, and the three valve ports of the liquid adding three-way solenoid valve are respectively connected to the sample bottle, the syringe and the liquid adding channel through hoses.

[0018] Preferably, the liquid adding needle is located at the bottom of the fixing seat, the fixing seat is provided with a through hole, the sampling needle passes through the through hole and extends into the sample tube in parallel with the liquid adding needle.

[0019] The beneficial effects of the present invention are:

[0020] 1. The present invention adopts a magnetic traction connection, by providing a hollow piston cavity in the guide rail and a walking slider on the outside, installing an internal magnetic mechanism (first magnet) in the piston cavity, and providing an external magnetic mechanism (second magnet) on the walking slider that is attracted to the internal magnetic mechanism, thereby forming a magnetic coordination structure through the internal magnetic mechanism and the external magnetic machine to achieve synchronous movement of the inner and outer components of the guide rail; the present invention replaces the general mechanical connection with a magnetic traction connection, reduces mechanical loss, and prolongs the service life.

[0021] Second, the present invention adopts the pneumatic transmission principle, and utilizes the airtight chamber and the air source assembly to drive the piston in the guide rail to reciprocate, thereby driving the external slider and the sampling needle to move synchronously. The present invention replaces the general mechanical transmission with pneumatic transmission, which not only saves space, reduces the overall weight, but also increases the safety of use.

[0022] 3. The present invention adopts a flexible design and utilizes flexible components such as hoses for installation to a large extent, reducing rigid connections. It can be flexibly arranged according to the space, greatly saving structural space, and the loss of the flexible design can be basically ignored, achieving no consumables. In addition, it can also achieve full sealing and improve corrosion resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall connection of a magnetic traction sampling system for pre-processing samples according to an embodiment of the present invention.

[0024] Figure 2 It is a schematic diagram of an exploded view of a magnetic traction sampling device for pre-processing samples according to an embodiment of the present invention.

[0025] Figure 3 It is a schematic diagram of the assembly of a magnetic traction sampling device for pre-processing samples according to an embodiment of the present invention.

[0026] Figure 4 It is a cross-sectional schematic diagram of a magnetic traction sampling device for pre-processing samples according to an embodiment of the present invention.

[0027] Figure 5 yes Figure 4 Enlarged view of point A in the middle.

[0028] Figure 6 yes Figure 4 Enlarged view of point B in the middle.

[0029] Figure 7 It is a cross-sectional schematic diagram of a slider according to an embodiment of the present invention.

[0030] Figure 8 It is a schematic axial view of a slider according to an embodiment of the present invention.

[0031] Fig. 9 It is a cross-sectional schematic diagram of a piston according to an embodiment of the present invention.

[0032] Fig.10 It is a schematic axial view of a magnetic induction module according to an embodiment of the present invention.

[0033] Fig.11 It is a top axial side schematic diagram of a fixed upper seat according to an embodiment of the present invention.

[0034] Fig.12 It is a bottom axial side schematic diagram of a fixed upper seat according to an embodiment of the present invention.

[0035] Fig.13 It is a schematic diagram of the top axis side of a fixed lower seat according to an embodiment of the present invention.

[0036] Fig.14 It is a cross-sectional schematic diagram of an upper limit block according to an embodiment of the present invention.

[0037] Fig.15 It is a connection diagram of a liquid adding component according to an embodiment of the present invention.

[0038] Fig.16 The present invention is a schematic diagram of the connection between a sampling needle, a sample tube, a peristaltic pump, a detector and a waste liquid bottle according to an embodiment of the present invention.

[0039] Fig.17 It is a connection diagram of an air source component according to an embodiment of the present invention.

[0040] Fig.18 It is a schematic structural diagram of an air intake pump (air outlet pump) according to an embodiment of the present invention.

[0041] Fig.19 It is a structural schematic diagram of a gas source three-way solenoid valve according to an embodiment of the present invention.

[0042] Description of labels:

[0043] Sampling device 1, slider 11, clamping portion 111, mounting portion 112, mounting hole 1121, second magnet fixing groove 113, third magnet fixing groove 114, guide rail 12, piston chamber 121, upper limit block 122, fixing pin connecting hole 1221, exhaust hole 1222, fixing pin 123, piston 13, sealing ring groove 131, piston sealing ring 132, first magnet fixing groove 133, first magnet 14, second magnet 15, fixing seat 16, mounting port 161, guide rail sealing ring 162, gas passage 163, gas port 164, fixing upper seat 165, fixing lower seat 166, fastener 167, liquid adding channel 168 , through hole 169, magnetic induction avoidance groove 170, sampling needle 17, air source assembly 18, air source three-way solenoid valve 181, normally closed port 1811, normally open port 1812, common port 1813, air inlet pump 182, air inlet port 1821, air outlet pump 183, air outlet port 1831, third magnet 19, magnetic induction module 20, magnetic induction contact 201, sampling system 100, liquid adding assembly 2, liquid adding three-way solenoid valve 21, normally closed port 211, normally open port 212, common port 213, sample bottle 22, syringe 23, liquid adding needle 3, sample tube 4, peristaltic pump 5, liquid extraction port 51, liquid discharge port 52, detector 6, waste liquid bottle 7. DETAILED DESCRIPTION

[0044] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] The present invention provides a pre-processed sample magnetic traction sampling device 1, such as Figure 2 As shown, it includes a slider 11, a guide rail 12, a piston 13, a first magnet 14, a second magnet 15, a fixing seat 16, a sampling needle 17, an air source assembly 18, a third magnet 19, and a magnetic induction module 20.

[0046] The fixing seat 16 has an installation opening 161, the shape of which is the same as the cross-sectional shape of the guide rail 12. The guide rail 12 is vertically inserted into the installation opening 161 and sealed by a guide rail sealing ring 162.

[0047] ; Combine Figures 4 to 6 The guide rail 12 is provided with a piston chamber 121, and the piston 13 (the piston 13 has a cross section as shown in Fig. 9 The side wall of the rotating body shown in FIG. 1 is provided with an annular sealing ring groove 131 for a piston sealing ring 132 to be sleeved, the piston 13 is sealed in the piston cavity 121, and a first magnet fixing groove 133 is provided on the upper part of the piston. The first magnet 14 is bonded in the first magnet fixing groove 133 with a strong glue, as shown in FIG. Figure 8 As shown, the slider 11 is provided with a clamping portion 111 and a mounting portion 112 (the cross section of the slider 11 is as shown in FIG. Figure 7As shown in the figure, the slider 11 is clamped and fitted on the guide rail 12 by the clamping part 111 and slides axially along the guide rail 12. The sampling needle 17 is installed on the mounting part 112 of the slider 11 (the slider mounting part 112 has a mounting hole 1121 for the sampling needle 17 to penetrate and fit). The mounting part 112 of the slider 11 has a second magnet fixing groove 113 at a position facing the first magnet 14. The second magnet 15 is bonded to the second magnet fixing groove 113 with strong glue. The second magnet 15 has opposite magnetic properties to the first magnet 14, so that the second magnet 15 and the first magnet 14 are attracted to each other. Figure 4 As shown in FIG. 1 , when the piston 13 slides axially along the guide rail 12, the second magnet 15 attracts the first magnet 14, so that the piston 13 can drive the outer slider 11 and the sampling needle 17 to slide axially along the guide rail 12 at the same time. To prevent the slider 11 from leaving the guide rail 12, an upper limit block 122 is provided on the top of the guide rail 12. Figure 2 and Fig.14 The upper limit block 122 has a piston cavity exhaust hole 1222 at the top for balancing the air pressure. The bottom of the upper limit block 122 is inserted into the guide rail 12, and the guide rail 12 and the bottom of the upper limit block 122 have a connected fixing pin connection hole 1221 at the same position for a fixing pin 123 to pass through, thereby completing the installation of the upper limit block on the guide rail. The present invention adopts a magnetic traction connection, by providing a hollow piston cavity 121 in the guide rail 12 and a slider 11 on the outside, installing an internal magnetic mechanism (first magnet) in the piston cavity 121, and providing an external magnetic mechanism (second magnet) on the slider 11 that is attracted to the internal magnetic mechanism, thereby forming a magnetic synergistic structure through the internal magnetic mechanism and the external magnetic machine, and realizing the synchronous movement of the inner and outer parts of the guide rail; the present invention replaces the general mechanical connection with a magnetic traction connection, reduces mechanical loss, and prolongs the service life.

[0048] The fixing seat 16 is provided with a gas passage 163, the gas passage 163 is connected with the piston cavity 121 to form an airtight chamber, the gas passage is provided with an air port 164, the gas source assembly 18 is connected with the air port 164 to introduce or discharge pressurized gas into the airtight chamber, thereby driving the piston 13 to move up and down, and further driving the slider 11 and the sampling needle 17 to feed up and down. The present invention replaces the general mechanical transmission with pneumatic transmission, which not only saves space, reduces the overall weight, but also increases the safety of use.

[0049] In one embodiment, if Fig.17 As shown, the gas source assembly 18 includes a gas source three-way solenoid valve 181, an air inlet pump 182 and an air outlet pump 183. Fig.19 As shown, the three valve ports of the gas source three-way solenoid valve 181 are respectively a normally closed port 1811, a normally open port 1812 and a common port 1813. Fig.17 and Fig.19The normally closed port 1811, the normally open port 1812 and the common port 1813 are connected to the air inlet pump 182, the air outlet pump 183 and the air port 164 through hoses. The air inlet pump 182 and the air outlet pump 183 can use the same type of vacuum pump, such as Fig.18 As shown, the vacuum pump is provided with an air inlet and an air outlet, therefore, the air inlet 1821 of the air inlet pump 182 is connected to the normally closed port 1811 of the air source three-way solenoid valve 181, and the air outlet 1831 of the air outlet pump 183 is connected to the normally open port 1812 of the air source three-way solenoid valve 181; the common port 1813 of the air source three-way solenoid valve 181 is connected to the air port 164 via a barbed joint.

[0050] like Figure 2 , Figures 11 to 13 As shown, the fixing seat 16 includes a fixing upper seat 165 , a fixing lower seat 166 and a fastener 167 . The fixing upper seat 165 is sealed and fixed above the fixing lower seat 166 by the fastener 167 , so that the user can disassemble and inspect the inside of the fixing seat 16 conveniently.

[0051] A pre-treatment sample magnetic traction sampling system comprises the above-mentioned pre-treatment sample magnetic traction sampling device 1, a liquid adding component 2, a liquid adding needle 3, a sample tube 4, a peristaltic pump 5, a detector 6 and a waste liquid bottle 7.

[0052] The liquid adding component 2 is composed of a liquid adding three-way solenoid valve 21, a sample bottle 22 and a syringe 23. The three valve ports of the liquid adding three-way solenoid valve 21 are respectively a normally closed port 211, a normally open port 212 and a common port 213. The fixed seat 16 is provided with a liquid adding channel 168. One end of the liquid adding channel 168 is connected to the normally closed port 211 through a hose, and the other end of the liquid adding channel is connected to the liquid adding needle 3. The common port 213 is connected to the syringe through a hose, and the normally open port 212 is connected to the sample bottle 22 through a hose, so that the liquid adding component adds liquid to the liquid adding needle through the liquid adding channel.

[0053] The liquid adding needle 3 is located at the bottom of the fixing seat 16, and the fixing seat 16 is provided with a through hole 169. The sampling needle 17 passes through the through hole 169 and extends into the sample tube 4 in parallel with the liquid adding needle 3. When the sampling needle 17 is fed downward, special attention should be paid to avoid the inner wall of the sample tube 4 being damaged or the sampling needle being bent due to operating errors. To prevent this from happening, the present invention is designed with a magnetic induction module 20 and a third magnet fixing groove 114 is provided at the bottom of the slider 11 for fixing to the third magnet 19. The magnetic induction module 20 is installed on the fixing seat 16 located directly below the third magnet 19 (specifically, inside the fixing seat 16, and a magnetic induction avoidance groove 170 is provided inside the fixing seat 16). , for the magnetic induction module 20 to be placed), the magnetic induction module 20 is electrically connected to the air source component 18, and a magnetic induction contact 201 is provided on the magnetic induction module 20. When the slider 11 moves down to the point where the third magnet 19 contacts the magnetic induction contact 201, the magnetic induction module 20 sends an intake signal to the air source component 18. The air source component 18 receives the intake signal and starts to pass pressurized gas into the airtight chamber. The pressurized gas squeezes the piston 13 to move upward, driving the slider 11 and the sampling needle 17 to stop moving downward and start to feed upward.

[0054] The sampling needle 17 is connected to the liquid extraction port 51 of the peristaltic pump 5 through a hose, the liquid discharge port 52 of the peristaltic pump is connected to the inlet of the detector 6 through a hose, and the outlet of the detector is connected to the waste liquid bottle 7 through a hose. The present invention adopts a flexible design as a whole, and uses flexible parts such as hoses for installation to a large extent, reducing rigid connections, and can be flexibly arranged according to space, greatly saving structural space, and the loss of the flexible design can be basically ignored, achieving no consumables, and can also achieve full sealing and improve corrosion resistance. In order to further improve the airtightness of the structure, the ends of the hoses described in this case all use barbed connectors to connect other parts.

[0055] The specific working process of the present invention is as follows: first, the syringe extracts the sample reagent from the sample bottle 22 through the common port 213 and the normally open port 212 of the liquid adding three-way solenoid valve 21, the normally closed port 211 of the liquid adding three-way solenoid valve 21 is opened, and the normally open port 212 is closed, and the syringe pushes the extracted sample reagent to the liquid adding channel 168 of the fixed seat 16, and then flows out to the sample tube 4 (the sample tube 4 can be a digestion tube) through the liquid adding channel 168 and the liquid adding needle, then, the air inlet pump 182 is closed, the air outlet pump 183 is started, the normally closed port 1811 of the air source three-way solenoid valve 181 is closed, and the normally open port 1812 is opened, and the pressure gas in the airtight chamber is gradually discharged to the air outlet pump, and the piston 13 moves downward, and the slider 11 drives the sampling needle 17 to feed downward into the sample tube 4; then, the peristaltic pump 5 is started, and the sample reagent in the sample tube 4 is extracted from the liquid extraction port 51, and discharged from the liquid discharge port 52 into the detector 6 for detection and analysis. Finally, after the sample detection is completed, when the air intake pump 182 is started, the normally closed port 1811 of the air source three-way solenoid valve 181 is opened and the normally open port 1812 is closed, and the air intake pump 182 begins to introduce pressurized gas into the airtight chamber through the air port 164, the piston 13 moves upward, and the slider 11 drives the sampling needle 17 to feed upward into the sample tube 4, the peristaltic pump 5 draws in air, and discharges the sample reagent in the detector 6 into the waste liquid bottle 7.

[0056] In the description of the present invention, it should be noted that the terms "top", "bottom", "up", "down", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0057] The above description is only a preferred embodiment of the present invention and is not a limitation on the design of this case. Any equivalent changes made based on the design key of this case shall fall within the protection scope of this case.

Claims

1. A pre-treatment sample traction type liquid addition sampling system, characterized in that: It includes a sampling device, a liquid adding component, a liquid adding needle, a sample tube, a peristaltic pump, a detector and a waste liquid bottle; the sampling device includes a slide block, a guide rail, a piston, a first magnet, a second magnet, a fixing seat, a sampling needle and an air source component; The guide rail is vertically mounted on the fixed seat, a piston cavity is arranged in the guide rail, the piston is sealed and fitted in the piston cavity, the first magnet is fixed on the piston, the slider is fitted on the guide rail and slides axially along the guide rail, the sampling needle is mounted on the slider, the second magnet is fixed on the slider, and the magnetic properties of the second magnet are opposite to those of the first magnet; A gas passage is provided in the fixing seat, the gas passage is connected with the piston cavity to form an airtight chamber, a gas port is provided in the gas passage, and the gas source assembly is connected to the gas port to introduce or discharge pressurized gas into the airtight chamber, thereby driving the piston to move up and down, and further driving the slider and the sampling needle to feed up and down; The fixing seat is provided with a liquid adding channel, one end of the liquid adding channel is connected to the liquid adding component through a hose, and the other end of the liquid adding channel is connected to the liquid adding needle, so that the liquid adding component adds liquid to the liquid adding needle through the liquid adding channel, the liquid adding needle and the sampling needle are inserted into the sample tube together, the sampling needle is connected to the liquid extraction port of the peristaltic pump through a hose, the liquid discharge port of the peristaltic pump is connected to the inlet of the detector through a hose, and the outlet of the detector is connected to the waste liquid bottle through a hose.

2. A pre-treatment sample pulling type liquid adding sampling system as claimed in claim 1, characterized in that: The liquid adding component is composed of a liquid adding three-way electromagnetic valve, a sample bottle and a syringe. The three valve ports of the liquid adding three-way electromagnetic valve are respectively connected to the sample bottle, the syringe and the liquid adding channel through hoses.

3. A pre-treatment sample pulling type liquid adding sampling system as claimed in claim 1, characterized in that: The liquid adding needle is located at the bottom of the fixing seat, a through hole is formed in the fixing seat, and the sampling needle passes through the through hole and extends into the sample tube in parallel with the liquid adding needle.

4. A pre-treatment sample pulling type liquid adding sampling system as claimed in claim 1, characterized in that: The sampling device also includes a third magnet and a magnetic induction module, wherein the third magnet is fixed at the bottom of the slider, and the magnetic induction module is installed on a fixed seat directly below the third magnet. The magnetic induction module is connected to the gas source assembly, and a magnetic induction contact is provided on the magnetic induction module. When the slider moves down to the point where the third magnet contacts the magnetic induction contact, the magnetic induction module sends an intake signal to the gas source assembly, and the gas source assembly receives the intake signal and starts to pass pressurized gas into the airtight chamber. The pressurized gas squeezes the piston upward, driving the slider and the sampling needle to stop moving downward and start feeding upward.

5. A pre-treatment sample pulling type liquid adding sampling system as claimed in claim 4, characterized in that: The fixing seat is also provided with a magnetic induction avoidance groove for placing the magnetic induction module.

6. A pre-treatment sample pulling type liquid adding sampling system as claimed in claim 1, characterized in that: The air source assembly comprises an air source three-way solenoid valve, an air inlet pump and an air outlet pump. The three valve ports of the air source three-way solenoid valve are respectively connected to the air inlet pump, the air outlet pump and the air port through hoses.

7. A pre-treatment sample pulling type liquid adding sampling system as claimed in claim 1, characterized in that: The slide block is provided with a mounting hole for the sampling needle to penetrate and fit into.

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