Floating type sampling needle device

Abstract

The utility model provides a floating type sampling needle device, which comprises a fixed support, a sampling needle, a fixed support and a movable support, wherein a vertical guide hole is formed in the fixed support; the upper part of the adapter is provided with a guide column, the guide column is slidably mounted in the guide hole, the middle part and the lower part of the adapter respectively extend to form threaded holes, the two threaded holes are communicated with each other in the adapter, and the threaded hole in the middle is used for being communicated with a sample channel; the elastic element is arranged between the adapter and the fixed bracket, so that the adapter has a downward movement trend; and the sampling needle is hermetically connected with the threaded hole in the lower part of the adapter. The elastic space is added in the sampling needle fixing structure, so that the sampling needle can be always in contact with the bottom of a sample container without damaging the container and the sampling needle during complete sampling, and the purpose of completely extracting a sample is achieved.

Description

Technical Field

[0001] The utility model relates to a full-automatic solid phase extractor, in particular to a floating sampling needle device therein. 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, fully automatic solid phase extraction technology 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. Therefore, it is widely used in the fields of medicine, food, environment, commodity inspection, and chemical industry.

[0003] The sampling needle devices used for sample (or organic solvent) extraction in the fully automatic solid phase extraction instruments currently on the market all use a rigid connection, that is, the steel sampling needle structure is directly fixed to the corresponding transmission structure or base through threads or other means. However, when extracting samples (or organic solvents), it is required that the end of the sampling needle can be as close to the bottom of the container containing the liquid sample (or organic solvent) as possible, so as to ensure that the liquid sample can be fully sampled by the sampling needle. Due to the rigid connection of the sampling needle and the fact that the container is generally made of glass or plastic, once the sampling needle sampling depth is not appropriate or the container consistency is poor, the end (tip) of the sampling needle is easy to directly pierce the bottom of the container, which may damage the container or sampling needle in severe cases, resulting in liquid leakage or equipment damage, and the inability to complete the experimental process. Utility Model Content

[0004] The purpose of the utility model is to solve and avoid the problem that, during the sampling process, the rigid connection structure of the sampling needle causes the end (tip) of the sampling needle to directly pierce the bottom of the container when the sampling depth of the sampling needle is not appropriate or the consistency of the glass (plastic) container is poor, resulting in container rupture and damage or bending of the sampling needle, and leakage of the sample (or organic solvent) liquid, which damages the equipment.

[0005] The technical solution adopted by the utility model is:

[0006] A floating sampling needle device, characterized in that it comprises:

[0007] A fixed bracket is formed with a vertical guide hole;

[0008] The adapter has a guide post on its upper portion, the guide post is slidably installed in the guide hole, and threaded holes are respectively extended from the middle and lower portions of the adapter, the two threaded holes are interconnected inside the adapter, and the threaded hole in the middle portion is used to connect the sample passage;

[0009] The elastic element is arranged between the adapter and the fixed bracket, so that the adapter has a downward movement tendency;

[0010] The sampling needle is sealed and connected to the threaded hole at the bottom of the adapter.

[0011] In the floating sampling needle device, the threaded hole in the middle of the adapter is connected to a flange joint through a sealing blade ring, and the flange joint is used to connect the sample passage.

[0012] In the floating sampling needle device, a sealing joint is installed outside the threaded hole at the bottom of the adapter through a sealing ring, and the sampling needle passes through the sealing joint and is fixed to the threaded hole at the bottom of the adapter.

[0013] In the floating sampling needle device, the elastic element is a compression spring, which is sleeved on the guide post of the adapter and compressed between the adapter and the fixed bracket.

[0014] In the floating sampling needle device, the compression spring is a multi-lead, double-flat-end stainless steel coil spring.

[0015] The floating sampling needle device, wherein a guide member is fixed on the fixed bracket by means of threads, and the guide member has the guide hole.

[0016] The floating sampling needle device, wherein a stepped hole is provided inside the guide member for nested installation of the compression spring.

[0017] In the floating sampling needle device, the fixed bracket is divided into two layers, the lower layer is used to install the adapter, and the upper layer is used to install the guide member.

[0018] The floating sampling needle device further comprises a limiting nail fixed on the fixed bracket, the tail end of which cooperates with the guide groove on the adapter to limit the floating stroke of the adapter.

[0019] The floating sampling needle device is made of a hollow stainless steel tube, and the end thereof has a chamfer and a notch.

[0020] The floating sampling needle device in the utility model realizes the conventional lifting sampling function in the solid phase extraction process when equipped with a matching motion mechanism. The key point is that an elastic space is added in the sampling needle fixing structure. When completely sampling, it can ensure that the sampling needle always keeps in contact with the bottom of the sample container without damaging the container and the sampling needle itself, so as to achieve the purpose of completely extracting the sample. When sampling multiple channels simultaneously (in parallel), the complete sampling of all channels is guaranteed to the maximum extent, and the problem of non-parallel sampling caused by inconsistent height of the bottom of the container is eliminated. It can also reduce the adjustment requirement of the sampling depth of the sampling needle (the depth can be within the elastic range), thereby reducing the difficulty of using the equipment. In addition, with different needle tip structural shapes and filter heads of different specifications, it can also complete the functions of cleaning the sample container and filtering the sample online. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a three-dimensional diagram of a floating sampling needle device.

[0022] Figure 2 It is a cross-sectional view of the floating sampling needle device.

[0023] Figure 3 yes Figure 2 A partial enlarged view of .

[0024] Explanation of the reference numerals: 1 - sampling needle; 2 - sealing joint; 201 - sealing ring; 3 - fixing bracket; 4 - guide piece; 5 - adapter; 6 - compression spring; 7 - flange joint; 701 - sealing blade ring; 8 - limiting pin. DETAILED DESCRIPTION

[0025] like Figure 1-Figure 3 As shown, the utility model provides a floating sampling needle device, comprising:

[0026] The fixed bracket 3 is the installation basis and the weighing basis;

[0027] The guide member 4 is preferably fixed to the fixing bracket 3 by screw threads and has a vertical guide hole;

[0028] The adapter 5 is T-shaped, with a guide post at the upper part, and threaded holes extending from the middle and lower parts respectively, the two threaded holes are connected to each other inside the adapter 5, wherein the guide post is slidably installed in the guide hole of the guide member 4, the threaded hole in the middle part is connected to the flange joint 7 through the sealing blade ring 701, which is used to connect the sample passage, and the outer part of the threaded hole in the lower part is installed with a sealing joint 2 through the sealing ring 201;

[0029] A sampling needle 1 passes through the sealing joint 2 and is fixed to a threaded hole at the bottom of the adapter 5;

[0030] The compression spring 6 is sleeved on the guide post of the adapter 5 and compressed between the guide 4 and the adapter 5, so that the adapter 5 has a downward movement tendency;

[0031] The limiting nail 8 is fixed on the fixing bracket 3, and its tail end cooperates with the guide groove on the adapter to limit the floating stroke of the adapter 5, and also prevents the adapter from rotating in the circumferential direction.

[0032] In the above embodiment, the compression spring 6 may be replaced by other elastic elements, such as a tension spring; the floating stroke of the adapter 5 may also be limited by the step shape of the adapter 5 itself (there is no need to arrange the limit pin 8).

[0033] in:

[0034] The sampling needle 1 is made of a hollow stainless steel tube, which is corrosion-resistant and suitable for occasions where organic solvents and corrosive liquids (samples) are used; the injection port end adopts a chamfered and notched structure, and the needle tip formed by the chamfer is convenient for puncturing the sealing gasket placed at the mouth of the container during sampling. The cross-groove notch can form a jet of cleaning liquid at the tip of the needle under the action of the pipeline pressure, thereby achieving the effect of cleaning the sample container.

[0035] The upper end of the sampling needle 1 is fixed to the adapter 5 through a thread, and a sealing joint 2 (equipped with a sealing ring 201) is installed on the outer diameter of the sampling needle 1 to ensure the sealing performance between the sampling needle 1 and the adapter 5, and to enable the sampling needle 1 to be quickly installed and removed.

[0036] The sealing joint 2 (sealing ring 201) is made of corrosion-resistant materials such as PP. The sealing joint 2 presses the sealing ring 201 mounted on the sampling needle 1 against its outer diameter and the end face of the adapter 5 through threads, so that the sampling needle 1 and the adapter 5 achieve a sealing effect.

[0037] The fixed bracket 3 is the installation reference and load-bearing structure of the device. It is made of aluminum alloy, which ensures the structural strength while reducing the overall weight of the device. The fixed bracket 3 is divided into two layers, the upper and lower layers, and the distance between the two layers is related to the floating stroke of the sampling needle 1. The hole in the lower layer is used to cooperate with the adapter 5 to provide a floating guide for the sampling needle 1; the upper layer adopts an open structure, mainly to facilitate the installation of the adapter 5, the compression spring 6 and other structures.

[0038] The guide member 4 has a stepped design inside to provide a positioning reference for the upper end of the compression spring 6; the guide member 4 is connected to the fixed bracket 3 through a thread, and a disassembly structure is reserved at the top.

[0039] The adapter 5 is made of stainless steel, which is corrosion-resistant and high-temperature-resistant, and is suitable for the analysis of various organic solvents and complex samples; the lower end is connected to the sampling needle 1 through an internal thread, and the internal pipeline can be set in radial and axial directions as needed (the direction shown in the figure is radial, perpendicular to the sampling needle 1), and the guide column at the upper end of the adapter 5 can be used to set the compression spring 6, which is convenient for the installation and fixation of the compression spring 6. A guide groove is provided on the outer circumference of the adapter 5 to limit the movement stroke and direction.

[0040] The compression spring 6 adopts a multi-lead double flat-end spiral structure and is made of corrosion-resistant and high-temperature resistant stainless steel to improve the service life while ensuring the performance. The compression spring 6 is installed between the internal step of the guide 4 and the adapter 5. Under the action of the compression spring 6, the lower end surface of the adapter 5 always keeps in contact with the upper end surface of the lower layer of the fixed bracket 3, and provides continuous elastic force output within the effective motion range.

[0041] The flange joint 7 is similar to the sealing joint 2, both of which are made of corrosion-resistant materials, and form a closed sample passage through the sealing blade ring 701 and the matching plastic pipeline. The threaded structure is used for easy installation and disassembly.

[0042] The assembly method of the floating sampling needle 1 device of the utility model is as follows:

[0043] Insert the lower end of the adapter 5 into the gap between the upper and lower layers of the fixed bracket 3, install the limit pin 8 on the lower layer of the fixed bracket 3, and align the guide groove on the adapter 5 with the limit pin 8;

[0044] Put the compression spring 6 into the guide post on the adapter 5 from the opening of the upper layer of the fixing bracket 3, then use the guide 4 to insert the upper end of the compression spring 6 into the internal step hole, and install the guide 4 on the threaded groove of the upper layer of the fixing bracket 3 through threads;

[0045] Screw the external thread at the top of the sampling needle 1 into the thread at the lower end of the adapter 5, insert the sealing ring 201 and the sealing joint 2 onto the sampling needle 1 in sequence, and fix them on the adapter 5 to ensure the sealed connection between the sampling needle 1 and the adapter 5; finally, put the sealing joint 2 and the sealing blade ring 701 onto the outlet pipeline in sequence, and fix them on the sample outlet thread of the adapter 5 to form a sample pipeline passage with sealing performance.

[0046] When the floating sampling needle 1 device provided by the utility model encounters the problem of inappropriate sampling depth of the sampling needle 1 or poor consistency of the glass (plastic) container during the sampling process, once the end (tip) of the sampling needle 1 pierces the bottom of the container, the compression spring 6 will be deformed under pressure to form an avoidance effect, and the container will not be broken or damaged, the sampling needle 1 will not bend, and there is no risk of leakage of the sample (or organic solvent) liquid; in addition, the overall structure of the utility model is simple and compact, the manufacturing process is simple, the structural stability is good, it is easy to install and maintain, and it is also conducive to modular design. It can form different configurations such as a single group of sampling needles 1 and multiple groups of sampling needles 1, and has good expansion and practicality.

Claims

1. A floating sampling needle device, characterized in that: include: A fixed bracket is formed with a vertical guide hole; The adapter has a guide post on its upper portion, the guide post is slidably installed in the guide hole, and threaded holes are respectively extended from the middle and lower portions of the adapter, the two threaded holes are interconnected inside the adapter, and the threaded hole in the middle portion is used to connect the sample passage; The elastic element is arranged between the adapter and the fixed bracket, so that the adapter has a downward movement tendency; The sampling needle is sealed and connected to the threaded hole at the bottom of the adapter.

2. The floating sampling needle device according to claim 1, characterized in that: The threaded hole in the middle of the adapter is connected with a flange joint through a sealing blade ring, and the flange joint is used to connect the sample passage.

3. The floating sampling needle device according to claim 1, characterized in that: A sealing joint is installed outside the threaded hole at the lower part of the adapter through a sealing ring, and the sampling needle passes through the sealing joint and is fixed to the threaded hole at the lower part of the adapter.

4. The floating sampling needle device according to claim 1, characterized in that: The elastic element is a compression spring, which is sleeved on the guide column of the adapter and compressed between the adapter and the fixed bracket.

5. The floating sampling needle device according to claim 4, characterized in that: The compression spring is a multi-lead, double-flat-end stainless steel helical spring.

6. The floating sampling needle device according to claim 4, characterized in that: A guide piece is fixed on the fixing bracket by screw threads, and the guide piece has the guide hole.

7. The floating sampling needle device according to claim 6, characterized in that: A stepped hole is arranged inside the guide member for nesting and installing the compression spring.

8. The floating sampling needle device according to claim 6, characterized in that: The fixing bracket is divided into two layers, the lower layer is used to install the adapter, and the upper layer is used to install the guide member.

9. The floating sampling needle device according to claim 1, characterized in that: It also includes a limiting nail fixed on the fixing bracket, the tail end of which cooperates with the guide groove on the adapter to limit the floating stroke of the adapter.

10. The floating sampling needle device according to claim 1, characterized in that: The sampling needle is made of a hollow stainless steel tube, and the end thereof is provided with a chamfer and a notch.

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