IVD precision micro-sampling needle with liquid level detection function
Patent Information
- Application Number
- CN202522506743.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-26
- Publication Date
- 2026-10-27
- Estimated Expiration
- 2035-11-26
AI Technical Summary
现有的取样针未在端部设置相应的保护措施，在实际使用过程中，存在有各种突发情况，例如取样针插入样本溶液过深导致针体端面与样本液体接触，使端面附着有样本液滴，或因操作不当导致取样针掉入盛放有样本的量杯中，此时内壁与外壁端面容易通过样本液体导通，由于内外壁存在有电压差且为金属材料，会在内外壁之间产生电流，形成电化学腐蚀，导致内壁外壁出现点蚀而逐渐产生腐蚀孔及空洞，使取样针逐渐失去功能，极大地缩短了取样针的使用寿命
本实用新型通过设置取样头，对针体的端面进行绝缘密封，以防止作为电容两极的针芯和外套管同时与样本液体意外接触，从而避免针芯与外套管质检产生电化学腐蚀，保护针体结构，可靠性高，能有效提升取样针的使用寿命；另外，取样头与针体通过相配合的螺纹构成可拆卸式连接，拆装方便，便于进行清洁工作，且取样头在安装的过程中可自动将弹性绝缘块压紧，实现可靠的密封连接，在安装过程中无需多余的操作，即可实现对针体的有效保护，操作简单，便于使用。
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Figure CN224906389U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of medical testing technology, and more specifically, to an IVD precision micro-sampling needle with liquid level detection function. Background Technology
[0002] IVD micro-sampling needles are core components in in vitro diagnostic devices used for collecting, transferring, and dispensing biological samples (such as blood, urine, reagents, etc.). The sampling needle has an internal channel for sample delivery, and its tip connects to an external device. The sample is collected and transferred by aspiration through the external device.
[0003] Currently, some sampling needles have liquid level detection capabilities. The specific method involves creating a voltage difference between the inner and outer tubes, forming a complete capacitance between the inner and outer walls of the needle. Liquid level detection and identification are achieved by detecting changes in capacitance between the inner and outer walls. Due to the need for conductivity, the inner and outer walls of the sampling needle must be made of conductive metal. Existing sampling needles lack appropriate protective measures at the tip. In actual use, various unforeseen situations can occur, such as the needle being inserted too deeply into the sample solution, causing the needle tip to come into contact with the sample liquid and leaving sample droplets on the tip. Or, due to improper operation, the sampling needle may fall into a measuring cup containing the sample. In these cases, the inner and outer walls can easily become conductive through the sample liquid. Because of the voltage difference between the inner and outer walls and the fact that they are made of metal, a current will be generated between them, leading to electrochemical corrosion. This causes pitting corrosion on both the inner and outer walls, gradually forming corrosion holes and voids, causing the sampling needle to gradually lose its function and significantly shortening its lifespan. Utility Model Content
[0004] The purpose of this invention is to provide an IVD precision micro-sampling needle with liquid level detection function that can effectively avoid electrochemical corrosion and has a long service life.
[0005] The objective of this utility model is achieved through the following technical solution.
[0006] An IVD precision micro-sampling needle with liquid level detection function includes: a needle body comprising a needle core, an insulating layer, and an outer tube arranged sequentially from the inside out, wherein the needle core has a sampling channel and both ends of the needle core extend beyond the insulating layer and the outer tube; a mounting block fitted onto the outside of the needle body, wherein the outer peripheral surface of the mounting block is threaded; and a sampling head comprising a connecting groove, a connecting hole, and an elastic insulating block, wherein the connecting groove is located at the end of the sampling head, the side wall of the connecting groove is threaded, the connecting hole is located within the connecting groove and extends through the sampling head along its thickness direction, the needle core is inserted into the connecting hole, and the elastic insulating block is located within the connecting groove, wherein the elastic insulating block has a hole for the needle core to pass through; wherein the sampling head is threadedly connected to the mounting block so that the end faces of the insulating layer and the outer tube press the elastic insulating block together.
[0007] In the above scheme, both the needle core and the outer tube are conductive, but separated by an insulating layer, thus creating a capacitance effect. The needle core, insulating layer, and outer tube together form a complete capacitor. When the end of the needle core contacts the sample, the capacitance changes due to the change in the medium. By detecting the capacitance change between the needle core and the outer tube, the system senses whether the needle core has touched the liquid surface, achieving the liquid surface detection function. The needle core has an internal sampling channel for sample passage. The length of the needle core is greater than the length of the insulating layer and the outer tube. Both ends of the needle core extend from inside the insulating layer and the outer tube; one end is used to connect to the pressure pump of an external instrument, and the other end is used to insert into the sample to achieve sample aspiration and complete the sampling process. The mounting block is fixedly fitted onto the needle body. The sampling head is threadedly connected to the mounting block fitted onto the needle body through a connecting groove at its end. The elastic insulating block has a hole for the needle core to pass through. The end of the needle core used for sample insertion passes through the elastic insulating block and the connecting hole in sequence, and then exits from the other end of the sampling head. In this design, the sampling head and mounting block are connected by a thread. During installation, the sampling head is screwed onto the mounting block. During installation, the elastic insulating block first contacts the end faces of the insulating layer and the outer sheath. Then, as the sampling head continues to rotate, the end faces of the insulating layer and the outer sheath gradually press the elastic insulating block together, forming a tight and reliable fit. This effectively ensures the insulation seal between the needle core and the outer sheath during sampling. Even if the sampling needle falls into the sample liquid in an emergency, the sealing effect of the elastic insulating block inside the sampling head effectively prevents the needle core and the outer sheath from simultaneously contacting the sample liquid, thus avoiding electrochemical corrosion. This application, by setting up a sampling head, protects the needle body from electrochemical corrosion, ensuring high reliability and effectively extending the service life of the sampling needle. Furthermore, the sampling head and needle body are connected by mating threads, forming a detachable connection that is convenient for assembly and disassembly, simple to operate, and facilitates cleaning of the sampling needle.
[0008] In one example of this utility model, both the sampling head and the mounting block are made of insulating material.
[0009] In the above scheme, all parts of the sampling head and mounting block are made of insulating material to prevent them from conducting with the needle core and outer tube, so as not to affect the accuracy of liquid level detection.
[0010] In one example of this invention, the projections of the insulating layer and the outer sleeve onto the elastic insulating block fall within the outline of the elastic insulating block.
[0011] In the above scheme, the vertical projection of the part of the needle body excluding the needle core falls within the outline of the elastic insulating block. That is, the width of the elastic insulating block is larger than that of the needle body, which ensures that the elastic insulating block can cover the entire insulation layer and the end face of the outer tube, ensuring full contact and guaranteeing the insulation and sealing effect between the needle core and the outer tube.
[0012] In one example of this utility model, a fixing groove is formed at the bottom of the connecting groove, and the elastic insulating block is fixedly installed in the fixing groove.
[0013] In the above scheme, the fixing groove is used to fix and limit the elastic insulating block, ensuring the stable installation of the elastic insulating component and preventing it from shifting, so as not to affect the docking installation with the needle body.
[0014] In one example of this utility model, the connecting hole is located within the fixing groove.
[0015] In the above scheme, the connecting hole is located in the fixing groove so that it can directly connect with the hole on the elastic insulating block, allowing the needle core to pass through, making the overall structure more compact.
[0016] In one example of this utility model, a positioning block is also included. The positioning block is provided with a mounting groove that mates with the needle body. The mounting groove is provided with a hole through which the needle core passes. The bottom surface of the mounting groove abuts against the end face of the insulating layer and the outer tube.
[0017] In the above scheme, the positioning block is fixedly sleeved on the outside of the needle body. The end of the needle body that connects to the pressure pump passes through a hole in the mounting groove. The end faces of the insulating layer and the outer sleeve abut against the bottom surface of the mounting groove. The mounting groove seals the end faces of the insulating layer and the outer sleeve to prevent electrochemical corrosion from occurring when the end of the needle body away from the sampling head falls into the sample solution or comes into contact with other liquids in case of an emergency, thus improving reliability. In addition, the positioning block can position the sampling needle when it is connected to external instruments (such as a sampling needle holder), which facilitates rapid positioning and installation of the sampling needle.
[0018] In one example of this utility model, an insulating sealing gasket is provided in the mounting groove, and the insulating sealing gasket abuts against the end face of the insulating layer and the outer sleeve.
[0019] In the above scheme, the end faces of the insulating layer and the outer sleeve press the insulating sealing gasket tightly into the mounting groove. By setting the insulating sealing gasket, the sealing performance between the mounting groove and the needle body can be further improved.
[0020] In one example of this utility model, both the needle core and the outer tube are made of stainless steel.
[0021] In the above scheme, stainless steel is conductive, which meets the requirement of forming a complete capacitance between the needle core and the outer sheath. In addition, stainless steel has strong corrosion resistance and biocompatibility, can adapt to complex chemical environments and high-temperature sterilization, and will not interfere with or affect the sample liquid.
[0022] In one example of this utility model, an external detection device is also included, which is electrically connected to the needle core and the outer sheath, respectively.
[0023] In the above scheme, the external detection equipment is electrically connected to the needle core and the outer tube to detect the change in capacitance between the needle core and the outer tube, so as to achieve the effect of liquid level detection.
[0024] Compared with the prior art, the beneficial effects of this utility model are as follows: This invention features a sampling head that insulates and seals the end face of the needle body to prevent the needle core and outer sheath, which act as the two poles of a capacitor, from accidentally contacting the sample liquid simultaneously. This avoids electrochemical corrosion between the needle core and outer sheath, protects the needle body structure, ensures high reliability, and effectively extends the service life of the sampling needle. Furthermore, the sampling head and needle body are connected by mating threads for a detachable connection, facilitating easy assembly and disassembly and cleaning. During installation, the sampling head automatically presses the elastic insulating block to achieve a reliable sealing connection. No additional steps are required during installation to effectively protect the needle body, making it simple and easy to use. Attached Figure Description
[0025] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0026] Figure 1 This is a cross-sectional view of an IVD precision micro-sampling needle according to an embodiment.
[0027] Figure 2for Figure 1 A magnified view of area A in the middle.
[0028] Figure 3 for Figure 1 A magnified view of area B in the middle.
[0029] Figure 4 This is a cross-sectional view of the sampling head.
[0030] Figure 5 This is a schematic diagram of sampling using an IVD precision micro-sampling needle.
[0031] Explanation of the reference numerals in the figure: 1-Needle body; 11-Needle core; 111-Sampling channel; 12-Insulation layer; 13-Outer tube; 2-Mounting block; 3-Sampling head; 31-Connecting groove; 32-Connecting hole; 33-Elastic insulating block; 34-Fixing groove; 4-Positioning block; 41-Mounting groove; 42-Insulating sealing gasket; 5-Measuring cup. Detailed Implementation
[0032] To facilitate understanding of this invention, a more comprehensive description will be provided below with reference to the accompanying drawings. The drawings illustrate preferred embodiments of the invention. However, this invention can be implemented in many different forms and is not limited to the embodiments described herein.
[0033] Please refer to Figures 1 to 4 An IVD precision micro-sampling needle with liquid level detection function includes a needle body 1, a mounting block 2, and a sampling head 3. The needle body 1 includes a needle core 11, an insulating layer 12, and an outer tube 13, which are sequentially arranged from the inside to the outside. The needle core 11 has a sampling channel 111 inside, and both ends of the needle core 11 extend beyond the insulating layer 12 and the outer tube 13. The mounting block 2 is sleeved on the outside of the needle body 1, and the outer peripheral surface of the mounting block 2 is threaded. The sampling head 3 includes a connecting groove 31, a connecting hole 32, and an elastic insulating block 33. The connecting groove 31 is located at the end of the sampling head 3, and the side wall of the connecting groove 31 is threaded. The connecting hole 32 is located in the connecting groove 31 and extends through the sampling head 3 along the thickness direction. The needle core 11 is inserted into the connecting hole 32, and the elastic insulating block 33 is located in the connecting groove 31. The elastic insulating block 33 has a hole for the needle core 11 to pass through. The sampling head 3 is threadedly connected to the mounting block 2 so that the end faces of the insulating layer 12 and the outer tube 13 press the elastic insulating block 33 tightly.
[0034] It should be noted that the needle core 11 and the outer sheath 13 are made of conductive material, while the insulating layer 12 is made of insulating material. The needle core 11 and the outer sheath 13 are separated by the insulating layer 12 and are not conductive, thus generating a capacitance effect. The needle core 11, the insulating layer 12, and the outer sheath 13 together form a complete capacitor, with the needle core 11 and the outer sheath 13 serving as the two terminals of the capacitor, respectively. When the end of the needle core 11 contacts the sample, the capacitance changes rapidly due to the change in the medium in which the needle core 11 is located. By detecting the capacitance change between the needle core 11 and the outer sheath 13, the system senses whether the needle core 11 has touched the liquid surface, thereby achieving the function of liquid surface detection.
[0035] Specifically, the needle core 11 has a sampling channel 111 inside for sample passage. The length of the needle core 11 is greater than the length of the insulating layer 12 and the outer tube 13. The upper and lower ends of the needle core 11 extend from inside the insulating layer 12 and the outer tube 13. Its top end is used to connect to the pressure pump of an external instrument, and its bottom end is used to insert into the sample. The pressure pump provides power to aspirate the sample, completing the sampling process. The mounting block 2 is fixedly sleeved on the needle body 1. The sampling head 3 is threadedly connected to the mounting block 2 sleeved on the needle body 1 through the connecting groove 31 at its end. The elastic insulating block 33 has a hole for the needle core 11 to pass through. The bottom end of the needle core 11 passes through the elastic insulating block 33 and the connecting hole 32 in sequence, and then exits from the other end of the sampling head 3. Since the sampling head 3 and the mounting block 2 are threadedly connected, the sampling head 3 is installed by screwing it onto the mounting block 2 during installation. During the screwing of the sampling head 3, the elastic insulating block 33 first contacts the lower end face of the insulating layer 12 and the outer sleeve 13. Then, as the sampling head 3 continues to rotate, the lower end face of the insulating layer 12 and the outer sleeve 13 gradually presses the elastic insulating block 33 into the connecting groove 31, forming a tight and reliable fit. This effectively ensures the insulation seal between the needle core 11 and the outer sleeve 13 during sampling. Even if a sudden situation occurs causing the sampling needle to fall into the sample liquid, submerging the sampling head 3, the sealing effect of the elastic insulating block 33 inside the sampling head 3 effectively prevents the needle core 11 and the outer sleeve 13 from simultaneously contacting the sample liquid, thus avoiding electrochemical corrosion. By setting the sampling head 3, the needle body 1 can be protected from electrochemical corrosion, ensuring high reliability and effectively extending the service life of the sampling needle. Furthermore, the sampling head 3 and the needle body 1 are connected by mating threads, making disassembly and assembly convenient, operation simple, and facilitating cleaning of the sampling needle.
[0036] It is worth mentioning that the bottom end face of the mounting block 2 is kept at a certain distance from the bottom end face of the outer sleeve 13, so as to ensure that when the end face of the insulating layer 12 and the outer sleeve 13 contacts the elastic insulating block 33, the mounting block 2 does not contact the bottom surface of the connecting groove 31, so as to ensure that the elastic insulating block 33 can fully and tightly contact the end face of the insulating layer 12 and the outer sleeve 13, and ensure the effect of insulation and sealing.
[0037] Preferably, both the needle core 11 and the outer sheath 13 are made of stainless steel. Stainless steel is conductive, which meets the requirement that the needle core 11 and the outer sheath 13 form a complete capacitor. In addition, stainless steel has strong corrosion resistance and biocompatibility, can adapt to complex chemical environments and high-temperature sterilization, and will not interfere with or affect the sample liquid.
[0038] Preferably, the elastic insulating block 33 is made of silicone rubber, which has good insulation, corrosion resistance, and biocompatibility, and a high elastic recovery rate. It can form a tight contact connection under pressure on the end face of the needle body 1, effectively ensuring sealing. In addition, other suitable materials such as butyl rubber and fluororubber can also be selected.
[0039] In this embodiment, both the sampling head 3 and the mounting block 2 are made of insulating material to prevent them from conducting with the needle core 11 and the outer sleeve 13, thus avoiding affecting the accuracy of liquid level detection. Furthermore, to ensure a stable connection between the sampling head 3 and the mounting block 2, forming a reliable rigid connection, both the sampling head 3 and the mounting block 2 must be rigid structures. While ensuring insulation, the sampling head 3 and the mounting block 2 can be made of materials such as PEEK, PPSU, PTFE, and PPS, and can be flexibly selected according to actual needs.
[0040] Please refer to Figure 2 The vertical projections of the insulating layer 12 and the outer sleeve 13 fall within the outline of the elastic insulating block 33. Specifically, in this embodiment, the elastic insulating block 33 is a ring structure, that is, the diameter of the elastic insulating block 33 is larger than the diameter of the needle body 1, so as to ensure that the elastic insulating block 33 can cover the entire end face of the insulating layer 12 and the outer sleeve 13, ensuring full contact with them, so as to ensure the insulation and sealing effect between the needle core 11 and the outer sleeve 13.
[0041] Please refer to Figure 1 , Figure 2 and Figure 4 The bottom of the connecting groove 31 has a fixing groove 34, in which the elastic insulating block 33 is fixedly installed. The fixing groove 34 is used to fix and limit the elastic insulating block 33, ensuring the stable installation of the elastic insulating component and preventing it from shifting, so as not to affect the docking installation with the needle body 1.
[0042] Furthermore, the connecting hole 32 is located within the fixing groove 34 so as to directly mate with the hole on the elastic insulating block 33, thereby allowing the needle core 11 to pass through directly, making the overall structure more compact.
[0043] Please refer to Figure 3 The needle body 1 is also provided with a positioning block 4. The positioning block 4 is provided with a mounting groove 41 that cooperates with the needle body 1. The mounting groove 41 is provided with a hole for the needle core 11 to pass through. The bottom surface of the mounting groove 41 abuts against the end face of the insulating layer 12 and the outer tube 13.
[0044] Specifically, the positioning block 4 is fixedly sleeved on the outside of the needle body 1. The top end of the needle body 1 passes through a hole provided in the mounting groove 41. The end faces of the insulating layer 12 and the outer sleeve 13 abut against the bottom surface of the mounting groove 41. The mounting groove 41 seals the upper end faces of the insulating layer 12 and the outer sleeve 13 to prevent electrochemical corrosion from occurring when the end of the needle body 1 away from the sampling head 3 falls into the sample solution or comes into contact with other liquids in case of an emergency, thus improving reliability. In addition, the positioning block 4 can position the sampling needle when it is connected to an external instrument (such as a sampling needle holder), which is beneficial for the rapid positioning and installation of the sampling needle. By using the positioning block 4 and the sampling head 3 to protect the upper and lower end faces of the needle body 1 respectively, the needle body 1 can be effectively protected from electrochemical corrosion, thus improving the service life of the sampling needle.
[0045] Furthermore, an insulating sealing gasket 42 is provided in the mounting groove 41. The insulating sealing gasket 42 abuts against the end faces of the insulating layer 12 and the outer sleeve 13. The upper end faces of the insulating layer 12 and the outer sleeve 13 press the insulating sealing gasket 42 tightly in the mounting groove 41. By providing the insulating sealing gasket 42, the sealing performance of the upper end face of the needle body 1 can be further guaranteed.
[0046] Preferably, the insulating sealing gasket 42 is also elastic to form a tight and reliable contact connection with the upper end face of the needle body 1, ensuring a seal. The specific material of the insulating sealing gasket 42 can be selected with reference to the material of the elastic insulating block 33.
[0047] In addition, this embodiment also includes an external detection device (not specifically shown in the figure). The external detection device is electrically connected to the needle core 11 and the outer tube 13 to detect the change in capacitance between the needle core 11 and the outer tube 13, thereby achieving the effect of liquid level detection. The external detection device can refer to the prior art, and will not be described in detail here.
[0048] like Figure 5 As shown, Figure 5 This is a schematic diagram of the sampling operation of this precision micro-sampling needle. The measuring cup 5 contains the sample solution to be sampled. First, the end of the sampling head 3 is immersed in the sample solution. Then, the suction force generated by the pressure pump is used to draw the sample solution in the measuring cup 5 into the external instrument through the sampling channel 111, thus completing the sampling operation.
[0049] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0050] Furthermore, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0051] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can be referred to each other.
[0052] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. An IVD precision micro-sampling needle with liquid level detection function, characterized in that, include: The needle body includes a needle core, an insulating layer, and an outer tube arranged sequentially from the inside out. The needle core has a sampling channel inside, and both ends of the needle core extend beyond the insulating layer and the outer tube. The mounting block is fitted onto the outside of the needle body, and the outer peripheral surface of the mounting block is provided with threads; A sampling head includes a connecting groove, a connecting hole, and an elastic insulating block. The connecting groove is located at the end of the sampling head, and the side wall of the connecting groove is provided with threads. The connecting hole is located in the connecting groove and extends through the sampling head along the thickness direction. The needle core is inserted into the connecting hole. The elastic insulating block is located in the connecting groove and has a hole for the needle core to pass through. The sampling head is threadedly connected to the mounting block so that the end faces of the insulating layer and the outer sleeve press the elastic insulating block together.
2. The IVD precision micro-sampling needle with liquid level detection function according to claim 1, characterized in that, Both the sampling head and the mounting block are made of insulating material.
3. The IVD precision micro-sampling needle with liquid level detection function according to claim 1, characterized in that, The projections of the insulating layer and the outer sleeve onto the elastic insulating block fall within the outline of the elastic insulating block.
4. The IVD precision micro-sampling needle with liquid level detection function according to claim 1, characterized in that, The bottom of the connecting groove has a fixing groove, and the elastic insulating block is fixedly installed in the fixing groove.
5. The IVD precision micro-sampling needle with liquid level detection function according to claim 4, characterized in that, The connecting hole is located inside the fixing groove.
6. The IVD precision micro-sampling needle with liquid level detection function according to claim 1, characterized in that, It also includes a positioning block, which has a mounting groove that mates with the needle body. The mounting groove has a hole through which the needle core passes, and the bottom surface of the mounting groove abuts against the end face of the insulating layer and the outer tube.
7. The IVD precision micro-sampling needle with liquid level detection function according to claim 6, characterized in that, An insulating sealing gasket is provided in the mounting groove, and the insulating sealing gasket abuts against the end face of the insulating layer and the outer sleeve.
8. The IVD precision micro-sampling needle with liquid level detection function according to claim 1, characterized in that, Both the needle core and the outer tube are made of stainless steel.
9. The IVD precision micro-sampling needle with liquid level detection function according to any one of claims 1-8, characterized in that, It also includes an external testing device, which is electrically connected to the needle core and the outer sheath, respectively.