Column insertion rod sealing device for liquid sampling

Abstract

The utility model provides a column inserting rod sealing device for liquid sampling, which comprises a joint fixing piece, a collecting needle, a piston main body and a sealing ring fixing piece, the upper part of the joint fixing piece is used for being connected with a mechanical arm, and the lower end of the joint fixing piece is communicated with an inner hole of the collecting needle; the upper end of the piston body is fixedly connected with the lower end of the connector fixing piece, and the lower end of the piston body is connected with the sealing ring fixing piece. The collecting needle can penetrate into the sealing ring fixing piece from top to bottom, the upper end of the sealing ring fixing piece is in sealing connection with the collecting needle, and the portion, extending out of the piston body, of the lower end of the sealing ring fixing piece is sleeved with an outer sealing ring. A boss structure capable of upwards extruding the outer sealing ring is arranged at the position, corresponding to the lower side of the outer sealing ring, of the sealing ring fixing piece. The column inserting rod device disclosed by the utility model can be easily inserted into an extraction column in a normal state, and when the column inserting rod device is inserted into the bottom, the sealing ring fixing piece moves upwards to extrude the outer sealing ring under a counter-acting force, so that the sealing and pressure-resistant performances are improved.

Description

Technical Field

[0001] The utility model relates to a full-automatic solid phase extractor in pre-treatment instrument equipment, in particular to an extraction column solvent sampling and collecting device in the full-automatic solid phase extractor. Background Art

[0002] Fully automatic solid phase extraction (SPE) is a sample pretreatment technology developed since the mid-1980s. It can be regarded as a combination of liquid-solid extraction columns and liquid chromatography technology. It is mainly used for sample separation, purification and concentration (enrichment). The main purpose is to reduce sample matrix interference and improve detection sensitivity. Compared with traditional liquid-liquid extraction, it can improve the recovery rate of analytes, more effectively separate analytes from interfering components, reduce sample pretreatment processes, and is simple to operate, time-saving and labor-saving. It is widely used in the fields of medicine, food, environment, commodity inspection, chemical industry, etc.

[0003] To ensure the precision and accuracy of the analysis results, most solid phase extraction instruments currently on the market use a column-inserted rod method for collection, ensuring that the sample is adsorbed by the solid at a uniform speed, avoiding the generation of bubbles during collection that may affect the analysis results.

[0004] However, when the column rod is in use, in order to ensure the sealing and pressure-resistant performance with the solid phase extraction column, the sealing ring and the inner wall of the extraction column are designed with sufficient interference. While ensuring the sealing, there is also the problem of difficulty in disassembly and assembly. Especially in the face of multi-channel high-throughput collection and sampling, a large thrust is required to insert the column rod into the extraction column. Therefore, a large torque motor is required when selecting the motor, which will cause certain waste in terms of space occupancy, power consumption and overall machine cost. At the same time, during use, there are also very high requirements for the positioning accuracy of the column rod and the extraction column. If there is a slight deviation in the positioning, the column rod cannot be inserted into the extraction column, which causes the sample to be discharged outside, resulting in waste, and even in severe cases, there is a risk of instrument damage. Utility Model Content

[0005] The purpose of the utility model is to provide a column rod sealing device for liquid sampling, which has a small friction resistance when inserted into an extraction column, can ensure multi-channel high-throughput sample collection, and can also ensure the stability of instrument operation, while also reducing the accuracy of extraction positioning.

[0006] The technical solution of the utility model is:

[0007] A column rod sealing device for liquid sampling, characterized in that it comprises a joint fixing part, a collecting needle, a piston body and a sealing ring fixing part, wherein:

[0008] The upper part of the joint fixing piece is used to connect with the robot arm, so that the upper end of the through hole inside the joint fixing piece is connected with the sample channel in the robot arm; the lower end of the through hole of the joint fixing piece is connected with the inner hole of the collection needle;

[0009] The piston body is a hollow structure and allows the collecting needle to pass through, and its upper end is fixedly connected to the lower end of the connector fixing piece, and its lower end is connected to the sealing ring fixing piece;

[0010] The sealing ring fixing piece allows the collecting needle to penetrate from top to bottom, the upper end of the sealing ring fixing piece forms a sealing connection with the collecting needle, the lower end of the sealing ring fixing piece extending out of the piston body is sleeved with an outer sealing ring, and the sealing ring fixing piece is provided with a boss structure capable of squeezing the outer sealing ring upward at a position corresponding to the lower side of the outer sealing ring.

[0011] The column rod sealing device for liquid sampling is described, wherein the upper portion of the joint fixing is provided with a first thread, the first thread is used to connect with the robotic arm; the lower outer side of the joint fixing is provided with a second thread, the second thread is used to install the piston body; the lower inner side of the joint fixing is provided with a third thread, the third thread is used to install the collecting needle.

[0012] The column rod sealing device for liquid sampling is characterized in that a groove is provided on the upper end surface of the joint fixing and a sealing gasket is placed thereon to ensure the sealing of the connection between the joint fixing and the robotic arm; or, the joint fixing is sealed and connected to the robotic arm by means of a rubber sealing ring or a blade ring.

[0013] In the column rod sealing device for liquid sampling, a boss is provided at the lower end of the first thread to control the verticality and positioning accuracy of the joint fixing member when it is installed on the mechanical arm.

[0014] The column plug sealing device for liquid sampling, wherein the bottom surface of the third thread is provided with a conical surface, and the collecting needle is fixed to the third thread of the joint fixing member through the joint and the blade ring seal;

[0015] Alternatively, the collecting needle is fixed to the joint fixing piece by laser welding.

[0016] The column rod sealing device for liquid sampling is described, wherein a groove structure is provided inside the lower end of the piston body for installing a spring and a sealing ring fixing piece, the spring is pressed against the top surface between the piston body and the sealing ring fixing piece, and positioning holes are provided on both sides of the lower end of the piston body, the positioning holes can be used for inserting and fixing a top screw, and the sealing ring fixing piece is provided with a positioning screw hole corresponding to the top screw.

[0017] The column rod sealing device for liquid sampling, wherein the spring is a multi-layer wave spring.

[0018] The column plug sealing device for liquid sampling, wherein a stepped groove is provided in the middle of the top of the sealing ring fixing piece, the deeper position of the stepped groove has a smaller diameter and an inner sealing ring is placed therein, and the shallower position of the stepped groove has a larger diameter and an inner thread is provided on the inner wall;

[0019] An inner fixing part is provided with a circular hole along the axial direction for penetrating the lower end of the collecting needle. The inner fixing part is provided with an external thread and connected with the internal thread of the stepped groove. By pressing the inner sealing ring, a sealed connection is formed between the piston body and the collecting needle.

[0020] The column rod sealing device for liquid sampling, wherein the top of the internal fixing member is provided with a hexagonal groove structure, a straight groove or a cross groove.

[0021] In the column rod sealing device for liquid sampling, the collecting needle is made of 316L stainless steel, or stainless steel with Teflon sprayed on it.

[0022] Compared with the extraction and collection methods of other products, the utility model has high experimental efficiency, is easy to operate, has good overall structural stability, is easy to operate, is conducive to modular design, better reduces the processing cost of the whole machine, and has good expansion and practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a stereoscopic diagram of the column plugging rod sealing device of the utility model.

[0024] Figure 2 It is a cross-sectional view of the column rod sealing device of the utility model (combined with a filter element and an extraction column).

[0025] Figure 3 It is a three-dimensional structural schematic diagram of the internal fixing part.

[0026] Figure 4 It is a three-dimensional structural schematic diagram of the sealing ring fixing part.

[0027] Figure 5 , Figure 6 They are schematic diagrams of the lower limit and upper limit abutment states of the top screw and the positioning screw hole respectively.

[0028] Explanation of the reference numerals: connector fixing part 1; first thread 101; second thread 102; third thread 103; groove 104; boss 105; conical concave surface 106; plane structure 107; through hole 108; collecting needle 2; inner hole 201; inclined surface structure 202; blade ring 3; connector 4; piston body 5; upper thread 501; hollow structure 502; groove structure 503; positioning hole 504; cutting plane structure 505; spring 6; inner fixing part 7; hexagonal groove structure 701; round hole 702; external thread 703; inner sealing ring 8; outer sealing ring 9; sealing ring fixing part 10; groove 1001; stepped groove 1002; inner thread 1003; positioning screw hole 1004; boss structure 1005; sealing gasket 11; top screw 12; extraction column 13. DETAILED DESCRIPTION

[0029] like Figure 1-Figure 3 As shown, the utility model provides a column rod sealing device for liquid sampling, comprising a joint fixing part 1, a collecting needle 2, a piston body 5 and a sealing ring fixing part 10, wherein:

[0030] The upper part of the joint fixing part 1 is provided with a first thread 101, and the first thread 101 is used to connect with the robot arm, so that the through hole 108 inside the joint fixing part 1 is connected with the sample channel in the robot arm; the lower outer side of the joint fixing part 1 is provided with a second thread 102, and the second thread 102 is used to install the piston body 5; the lower inner side of the joint fixing part 1 is provided with a third thread 103, and the third thread 103 is used to install the collection needle 2, so that the inner hole 201 of the collection needle 2 is connected with the through hole 108 inside the joint fixing part 1;

[0031] In addition, a groove 104 is provided on the upper end surface of the joint fixing member 1 and a sealing gasket 11 is placed thereon to ensure the sealing of the connection between the joint fixing member 1 and the robot arm and prevent the sample from being discharged to the outside;

[0032] A boss 105 is provided at the lower end of the first thread 101 to control the verticality and positioning accuracy of the joint fixing member 1 when it is installed on the robot arm;

[0033] Plane structures 107 are processed on both sides of the cylindrical surface of the joint fixing member 1 to ensure that the joint fixing member 1 can be locked and fixed by tools such as a wrench when installing;

[0034] The bottom surface of the third thread 103 is provided with a conical concave surface 106. When the collecting needle 2 is installed, the collecting needle 2 is sealed and fixed to the third thread 103 of the joint fixing member 1 through the joint 4 and the blade ring 3. The locking joint 4 can squeeze the blade ring 3 so that the blade ring 3 closes at the conical surface position to form a seal.

[0035] The upper end of the piston body 5 is provided with an upper thread 501 for connecting the second thread 102 of the joint fixing member 1, the middle is a hollow structure 502 for avoiding the locking joint 4 and the collecting needle 2, the lower end is provided with a groove structure 503 for installing the spring 6 and the sealing ring fixing member 10, and the lower end of the piston body 5 is provided with positioning holes 504 on both sides, and the positioning holes 504 can be inserted and fixed with the top screw 12 to limit the up and down travel of the sealing ring fixing member 10; the outer wall of the piston body 5 is provided with a cutting plane structure 505 on both sides, which can be locked and reinforced with an open-end wrench;

[0036] A groove 1001 is provided on the top surface of the sealing ring fixing part 10, which is used to abut against the lower end of the spring 6, and the upper end of the spring 6 is upwardly pressed against the piston body 5; a stepped groove 1002 is provided in the middle of the top of the sealing ring fixing part 10, the deeper position of the stepped groove 1002 has a smaller diameter and an inner sealing ring 8 is placed, and the inner wall of the shallower position of the stepped groove 1002 is provided with an internal thread 1003; the sealing ring fixing part 10 is provided with a positioning screw hole 1004 corresponding to the top screw 12, and the positioning screw hole 1004 has a lower limit 10041 and an upper limit 10042, which are used to limit the up and down movement position of the sealing ring fixing part 10 (such as Figure 5 , Figure 6 shown);

[0037] The top of the inner fixing member 7 is provided with an inner hexagonal groove structure 701, which can be locked and fixed using an inner hexagonal wrench. The inner fixing member 7 is provided with a circular hole 702 along the axial direction for inserting the lower end of the collecting needle 2. The inner fixing member 7 is also provided with an outer thread 703 and connected with the inner thread of the sealing ring fixing member 10. By pressing the inner sealing ring 8, a sealed connection is formed between the piston body 5 and the collecting needle 2.

[0038] The lower end of the sealing ring fixing member 10 is sleeved with an outer sealing ring 9, and a boss structure 1005 is formed at the lower position of the sealing ring fixing member 10 corresponding to the outer sealing ring 9. The bottom surface of the sealing ring fixing member 10 has an inverted cone structure 1006, which can increase the contact area between the solvent and the filler in the extraction column, and effectively improve the efficiency of sampling and collection;

[0039] The lower end of the collecting needle 2 is provided with a bevel structure 202, which has a guiding function when assembling the inner sealing ring 8 and prevents the inner ring of the inner sealing ring 8 from being cut when installing the inner sealing ring 8. At the same time, the bevel structure 202 of the collecting needle 2 can effectively prevent the solvent from hanging on the wall, effectively reducing the solvent residue on the collecting needle.

[0040] The utility model has the advantages that: the column insertion device of the utility model is in normal state (such as Figure 5 As shown in FIG. 1 , the piston body 5 can be easily inserted into the extraction column 13. When the piston body 5 is inserted downward to the bottom of the extraction column 13 (as shown in FIG. 1 ), the piston body 5 can be easily inserted into the extraction column 13. Figure 2As shown in FIG. 1 , the sealing ring fixing member 10 is subjected to the reaction force, and moves upward and squeezes the outer sealing ring 10 with the boss structure 1005, so that the outer sealing ring 10 expands and deforms (as shown in FIG. 1 ). Figure 6 When the piston body 5 is pulled out of the extraction column 13, the spring 6 has a restoring force to push the sealing ring fixing member 5 outward, so that the boss structure 1005 no longer squeezes the outer sealing ring 10, so as to reduce the friction between the outer sealing ring 10 and the inner wall of the extraction column 13.

[0041] In the above embodiment, the spring 6 preferably adopts a multi-layer wave spring, which can reduce the compression stroke of the spring 6 while ensuring sufficient thrust, and can also be replaced by a cylindrical or rectangular spring; in addition, the spring 6 can also be removed, and the outer sealing ring 10 can be reset by relying on its own elasticity to ensure that the column rod will not be affected by the resistance of the outer sealing ring 10 when it is separated from the extraction column 13.

[0042] In the above embodiment, the joint fixing member 1 is sealed and installed with the robot arm by using a sealing gasket 11, and in fact, it can also be sealed by using a rubber sealing ring or a blade ring.

[0043] In the above embodiment, the connector fixing member 1 seals the collecting needle 2 by means of the connector 4 and the blade ring 3. In fact, the collecting needle 2 may also be fixed to the connector fixing member 1 by means of laser welding.

[0044] In the above embodiment, the collecting needle 2 has a (single) bevel structure 202 at the lower end, which is convenient for installation with the inner sealing ring 8 and can also avoid liquid residue. In fact, the bevel structure 202 at the lower end can also be expanded into a conical structure (double bevel).

[0045] In the above embodiment, the collecting needle 2 is made of 316L stainless steel with good corrosion resistance. In fact, it can also be made of stainless steel with Teflon sprayed on it.

[0046] In the above embodiment, the sealing gasket 11 is made of PEEK material with strong corrosion resistance, and can also be made of PP and other materials.

[0047] In the above embodiment, the inner sealing ring 8 and the outer sealing ring 9 are made of FFKM material, which can meet the experimental requirements of perfluorinated compounds, and can also be made of high-fluorine material with good corrosion resistance.

[0048] In the above embodiment, the inner sealing ring 8 and the outer sealing ring 9 adopt an O-shaped sealing ring structure, and can also be made into a star-shaped sealing ring or a Y-shaped sealing ring structure.

[0049] In the above embodiment, the hexagonal groove structure 701 at the top of the internal fixing member 7 may also be replaced by a slot or a cross slot.

Claims

1. A column rod sealing device for liquid sampling, characterized in that: It includes a connector fixing part, a collecting needle, a piston body and a sealing ring fixing part, wherein: The upper part of the joint fixing piece is used to connect with the robot arm, so that the upper end of the through hole inside the joint fixing piece is connected with the sample channel in the robot arm; the lower end of the through hole of the joint fixing piece is connected with the inner hole of the collection needle; The piston body is a hollow structure and allows the collecting needle to pass through, and its upper end is fixedly connected to the lower end of the connector fixing piece, and its lower end is connected to the sealing ring fixing piece; The sealing ring fixing piece allows the collecting needle to penetrate from top to bottom, the upper end of the sealing ring fixing piece forms a sealing connection with the collecting needle, the lower end of the sealing ring fixing piece extending out of the piston body is sleeved with an outer sealing ring, and the sealing ring fixing piece is provided with a boss structure capable of squeezing the outer sealing ring upward at a position corresponding to the lower side of the outer sealing ring.

2. The column rod sealing device for liquid sampling according to claim 1, characterized in that: The upper part of the joint fixing piece is provided with a first thread, and the first thread is used to connect with the robot arm; the lower outer side of the joint fixing piece is provided with a second thread, and the second thread is used to install the piston body; the lower inner side of the joint fixing piece is provided with a third thread, and the third thread is used to install the collecting needle.

3. The column rod sealing device for liquid sampling according to claim 2, characterized in that: The upper end surface of the joint fixing piece is provided with a groove and a sealing gasket is placed thereon to ensure the sealing of the connection between the joint fixing piece and the robot arm; alternatively, the joint fixing piece is sealed and connected to the robot arm by means of a rubber sealing ring or a blade ring.

4. The column rod sealing device for liquid sampling according to claim 2, characterized in that: A boss is provided at the lower end of the first thread to control the verticality and positioning accuracy of the joint fixing member when it is installed on the mechanical arm.

5. The column rod sealing device for liquid sampling according to claim 2, characterized in that: The bottom surface of the third thread is provided with a conical surface, and the collecting needle is fixed to the third thread of the joint fixing member through the joint and the blade ring seal; Alternatively, the collecting needle is fixed to the joint fixing piece by laser welding.

6. The column rod sealing device for liquid sampling according to claim 1, characterized in that: A groove structure is provided inside the lower end of the piston body for installing a spring and a sealing ring fixing part. The spring is pressed against the top surface between the piston body and the sealing ring fixing part. Positioning holes are provided on both sides of the lower end of the piston body. The positioning holes can be used for inserting and fixing the top screw. The sealing ring fixing part is provided with a positioning screw hole corresponding to the top screw.

7. The column rod sealing device for liquid sampling according to claim 6, characterized in that: The spring is a multi-layer wave spring.

8. The column rod sealing device for liquid sampling according to claim 1, characterized in that: A stepped groove is provided in the middle of the top of the sealing ring fixing piece, the deeper part of the stepped groove has a smaller diameter and an inner sealing ring is placed therein, while the shallower part of the stepped groove has a larger diameter and an inner thread is provided on the inner wall; An inner fixing part is provided with a circular hole along the axial direction for penetrating the lower end of the collecting needle. The inner fixing part is provided with an external thread and connected with the internal thread of the stepped groove. By pressing the inner sealing ring, a sealed connection is formed between the piston body and the collecting needle.

9. The column rod sealing device for liquid sampling according to claim 8, characterized in that: The top of the internal fixing piece is provided with a hexagonal groove structure, a slot or a cross slot.

10. The column rod sealing device for liquid sampling according to claim 1, characterized in that: The collecting needle is made of 316L stainless steel, or stainless steel with Teflon sprayed on it.

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