A micro-injection needle structure

Abstract

The utility model discloses a kind of micro-injection needle structure, including needle cylinder, the inside of the needle cylinder is provided with driving assembly, the driving assembly includes piston, push rod, limit sleeve, four limit sliding blocks, threaded rod, threaded sleeve, driving ring and bearing;The piston is fixedly connected to the bottom end of threaded rod by push rod.This utility model is rotated driving ring, driving ring drives threaded sleeve to rotate, threaded sleeve drives threaded rod by screw action, threaded rod moves by push rod and promotes piston to move in needle cylinder, when piston is pulled upward, negative pressure is generated in needle cylinder, liquid is accurately extracted, when piston is pushed downward, liquid is accurately discharged;By rotating driving ring, the lifting of piston can be accurately controlled, by using threaded driving mode to replace traditional pull-out type driving, control precision is improved, especially in micro-sampling scene, avoid the precision deviation caused by operation force difference.

Description

Technical Field

[0001] This utility model relates to a sample injection needle structure, specifically a micro-volume sample injection needle structure, and belongs to the field of micro-volume sample injection needle technology. Background Technology

[0002] Manual micro-syringes are commonly used tools in chromatographic and experimental analysis. In chromatographic analysis, micro-syringes are used to extract a certain amount of the liquid sample to be analyzed and inject it into the chromatograph. In experimental analysis, they are often used to extract a certain amount of standard stock solution for the preparation of a series of standard solutions. Currently, the sampling method of micro-syringes is to first extract a volume of liquid larger than the required volume into the syringe, then remove the excess liquid to the required volume by observing the graduations on the syringe, and finally push the plunger to the zero line to transfer the liquid to the target instrument or container.

[0003] A Chinese utility model patent (publication number: CN219475085U) discloses a micro-volume injection needle, which has a mark embedded at the lower end of the plunger. When the micro-volume injection needle draws a certain amount of liquid, it first uses the end plane of the lower end of the plunger for preliminary positioning, and then aligns the mark at the lower end of the plunger with the corresponding scale line on the syringe for further precise quantification. This avoids the problem of inaccurate volume extraction due to the unclear boundary of the end plane of the lower end of the plunger and the difficulty in aligning it with the scale line on the syringe. By marking the piston part of the push rod, it significantly improves the intuitiveness and basic accuracy of sampling from a visual aid perspective. However, the core principle of sample extraction still relies on the traditional manual pulling of the push rod. The operator needs to pull the push rod with hand force to create negative pressure inside the injection needle, thereby drawing the sample into the syringe. However, different operators have different hand strength and force application habits. Even the same operator may experience changes in pulling force due to hand fatigue after prolonged operation, making it impossible for the push rod to stop precisely in the position that matches the mark. Ultimately, the sampling accuracy is greatly affected by the force of human operation, making it difficult to achieve highly consistent and accurate sampling results. This accuracy deviation caused by the force of operation is more obvious, especially in the sampling of micro or trace samples. Therefore, a micro-injection needle structure is proposed. Utility Model Content

[0004] The purpose of this invention is to provide a micro-injection needle structure to solve one of the problems mentioned in the background art.

[0005] This utility model is implemented by the following technical solution: a micro-injection needle structure, including a syringe, the inside of which is provided with a driving component, the driving component including a piston, a push rod, a limiting sleeve, four limiting sliders, a threaded rod, a threaded sleeve, a driving ring and a bearing; The piston is fixedly connected to the bottom end of the threaded rod via a push rod. Four sliding grooves are symmetrically opened on the outer side wall of the threaded rod. The four limiting sliders are symmetrically fixedly connected to the inner side wall of the limiting sleeve. The limiting sleeve is sleeved on the outside of the threaded rod and fixedly connected to the top of the inner side wall of the syringe. The threaded sleeve is fixedly connected to the inner side wall of the drive ring. The drive ring is sleeved on the outside of the syringe and rotatably connected to the top of the outer side wall of the syringe via a bearing.

[0006] As a further preferred embodiment of this technical solution: the inner wall of the threaded sleeve is threadedly connected to the outer wall of the threaded rod.

[0007] As a further preferred embodiment of this technical solution: the limiting slider is slidably connected to the inner wall of the groove.

[0008] As a further preferred embodiment of this technical solution: the piston is located inside the syringe and is in contact with the inner wall of the syringe.

[0009] As a further preferred embodiment of this technical solution, a marking line is provided on the bottom of the outer side wall of the piston.

[0010] As a further preferred embodiment of this technical solution, the outer wall of the syringe is provided with scale lines.

[0011] As a further preferred embodiment of this technical solution: the bottom of the syringe is provided with a water outlet pipe, and the water outlet pipe and the syringe are an integrated structure.

[0012] As a further preferred embodiment of this technical solution: a needle tube is sleeved on the outside of the water outlet pipe.

[0013] Advantages of this utility model: 1. This utility model uses a rotating drive ring to drive the threaded sleeve to rotate. The threaded sleeve drives the threaded rod through the thread action. With the cooperation of the limiting slider and the sliding groove, the threaded rod can move linearly relative to the threaded sleeve. When the threaded rod moves, it pushes the piston to move in the syringe through the push rod. When the piston is pulled upward, a negative pressure is generated in the syringe, and the liquid is accurately drawn in. When the piston is pushed downward, the liquid is accurately discharged. 2. This utility model can precisely control the lifting and lowering of the piston by rotating the drive ring. By adopting a threaded drive method instead of the traditional pull-out drive, the control accuracy is improved. Especially in micro-sampling scenarios, it avoids accuracy deviations caused by differences in operating force. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is an exploded view of the structure of this utility model; Figure 3 This is a schematic diagram of the limiting sleeve structure of this utility model; Figure 4 This is a schematic diagram of the connection between the threaded sleeve and the drive ring of this utility model; Figure 5 This is a cross-sectional view of the present invention.

[0016] In the diagram: 101, drive assembly; 11, syringe; 12, scale line; 13, piston; 131, marking line; 14, push rod; 15, limit sleeve; 16, limit slider; 17, threaded rod; 18, slide groove; 19, threaded sleeve; 20, drive ring; 21, bearing; 31, needle tube; 32, water outlet tube. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] Example Please see Figures 1-5 This utility model provides a technical solution: a micro-injection needle structure, including a syringe 11, and a drive assembly 101 is provided inside the syringe 11. The drive assembly 101 includes a piston 13, a push rod 14, a limiting sleeve 15, four limiting sliders 16, a threaded rod 17, a threaded sleeve 19, a drive ring 20, and a bearing 21. The piston 13 is located inside the syringe 11 and fits against the inner wall of the syringe 11. The outer wall of the piston 13 is equipped with a rubber or polymer sealing ring, and the sealing ring achieves dynamic sealing on the inner wall of the syringe 11, which plays the role of sealing and pushing / pulling liquid. The piston 13 is fixedly connected to the bottom end of the threaded rod 17 via the push rod 14. The threaded sleeve 19 is fixedly connected to the inner wall of the drive ring 20. The drive ring 20 is sleeved on the outside of the syringe 11 and is rotatably connected to the top of the outer wall of the syringe 11 via the bearing 21. The inner wall of the threaded sleeve 19 is threadedly connected to the outer wall of the threaded rod 17. The drive ring 20 drives the threaded sleeve 19 to rotate. The threaded sleeve 19 drives the threaded rod 17 through the thread action, thereby realizing the lifting and lowering control of the threaded rod 17. During the liquid sampling process, the threaded rod 17 performs a lifting action, which drives the piston 13 through the push rod 14. When the piston 13 moves upward, the liquid sampling operation is completed, and when the piston 13 moves downward, the liquid is discharged. The lifting and lowering of the piston 13 can be precisely controlled by rotating the drive ring 20. By using a threaded drive method instead of the traditional pull-out drive, the control accuracy is improved, especially in micro-sampling scenarios, avoiding accuracy deviations caused by differences in operating force. Through a fine thread design (such as a fine thread), micron-level displacement control can be achieved, thereby achieving microliter or even nanoliter-level injection accuracy. It is suitable for high-precision small-volume liquid sampling, but not suitable for large-volume liquid sampling.

[0019] Four grooves 18 are symmetrically provided on the outer side wall of the threaded rod 17. Four limiting sliders 16 are symmetrically fixedly connected to the inner side wall of the limiting sleeve 15. The limiting sleeve 15 is fitted on the outside of the threaded rod 17 and is fixedly connected to the top of the inner side wall of the syringe 11. The limiting sliders 16 are slidably connected to the inner side wall of the grooves 18. Through the precise cooperation between the limiting sliders 16 and the grooves 18, the limiting and guiding function can be realized. When the threaded sleeve 19 rotates to drive the threaded rod 17, the threaded rod 17 slides under the guidance of the limiting sliders 16 and does not rotate itself, thereby ensuring the effective driving of the piston 13.

[0020] In this embodiment, specifically: the outer wall of the syringe 11 is provided with scale lines 12, and the syringe 11 is made of highly transparent glass or plastic. The scale lines 12 on its outer wall can be used to visually display the volume of the liquid. The bottom of the outer wall of the piston 13 is provided with a mark 131. By aligning the mark 131 with the scale line 12, the current sampling amount can be read, thereby improving the intuitiveness and basic accuracy of sampling from a visual aid perspective.

[0021] In this embodiment, specifically: a water outlet tube 32 is provided at the bottom of the syringe 11. The water outlet tube 32 and the syringe 11 are an integrated structure. A needle tube 31 is sleeved on the outside of the water outlet tube 32. The needle tube 31 is the part that actually contacts the sample and can be replaced with different specifications as needed.

[0022] In terms of working principle or structural principle, when in use, the user rotates the drive ring 20 that is sleeved on the outside of the syringe 11 with their finger. The drive ring 20 drives the threaded sleeve 19 to rotate. The threaded sleeve 19 drives the threaded rod 17 through the thread action. With the cooperation of the limit slider 16 and the slide groove 18, the threaded rod 17 can move linearly relative to the threaded sleeve 19. When the threaded rod 17 moves, it pushes the piston 13 to move inside the syringe 11 through the push rod 14. When the piston 13 is pulled upward, a negative pressure is generated inside the syringe 11, and the liquid is accurately drawn in. When the piston 13 is pushed downward, the liquid is accurately discharged. Compared with the prior art, this utility model can precisely control the lifting and lowering of the piston 13 by rotating the drive ring 20. By adopting a threaded drive method instead of the traditional pull-out drive, the control accuracy is improved, especially in micro-sampling scenarios, avoiding accuracy deviations caused by differences in operating force.

[0023] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A micro-volume injection needle structure, characterized in that, Includes a syringe (11), inside which a drive assembly (101) is provided. The drive assembly (101) includes a piston (13), a push rod (14), a limiting sleeve (15), four limiting sliders (16), a threaded rod (17), a threaded sleeve (19), a drive ring (20), and a bearing (21). The piston (13) is fixedly connected to the bottom end of the threaded rod (17) via the push rod (14). The outer side wall of the threaded rod (17) is symmetrically provided with four sliding grooves (18). The four limiting sliders (16) are symmetrically fixedly connected to the inner side wall of the limiting sleeve (15). The limiting sleeve (15) is sleeved on the outside of the threaded rod (17) and fixedly connected to the top of the inner side wall of the syringe (11). The threaded sleeve (19) is fixedly connected to the inner side wall of the drive ring (20). The drive ring (20) is sleeved on the outside of the syringe (11) and rotatably connected to the top of the outer side wall of the syringe (11) via the bearing (21). The inner wall of the threaded sleeve (19) is threaded to the outer wall of the threaded rod (17), and the limiting slider (16) is slidably connected to the inner wall of the groove (18).

2. The micro-injection needle structure according to claim 1, characterized in that, The piston (13) is located inside the syringe (11) and is in contact with the inner wall of the syringe (11).

3. The micro-injection needle structure according to claim 1, characterized in that, The piston (13) has a marking (131) on the bottom of its outer side wall.

4. The micro-injection needle structure according to claim 1, characterized in that, The syringe (11) has scale lines (12) on its outer wall.

5. The micro-injection needle structure according to claim 1, characterized in that, The syringe (11) is provided with a water outlet pipe (32) at the bottom, and the water outlet pipe (32) and the syringe (11) are an integrated structure.

6. The micro-injection needle structure according to claim 5, characterized in that, The water outlet pipe (32) is fitted with a needle tube (31).

Images