Manufacturing process of a CGM guide needle

Abstract

The present invention relates to the technical field of surgical instruments, and in particular discloses a manufacturing process for a CGM guide needle, comprising the following steps: S1, installing a stamping die on a punch press, adjusting parameters, and fixing a cleaned metal raw material sheet in a lower die positioning device; S2, utilizing the wedge-shaped cutting edge of the upper die and the wedge-shaped protrusion of the lower die to punch out one end of the metal raw material sheet to form a sharp needle tip; S3, utilizing a first trimming punch to punch out the end of the metal raw material sheet close to the needle tip, forming chamfered portions on both sides; S4, utilizing the symmetrical protrusions of the upper die to stamp out a pre-crease in the middle of the metal raw material sheet, and then utilizing left and right dies to squeeze both sides of the pre-crease, so that the metal raw material sheet is folded to form two bent portions, and a needle groove is formed between the two, thereby obtaining a guide needle having a needle tip, a chamfered portion, and a needle groove; S5, utilizing a stripping die to remove the formed guide needle from the die, performing surface treatment, and then entering the next process.

Description

Technical Field

[0001] The present invention relates to the technical field of surgical instruments, and in particular discloses a manufacturing process of a CGM guide needle. Background Art

[0002] CGM (Continuous Glucose Monitoring) introducer needles are key components used to directly puncture the skin to implant the sensor. The manufacturing process for these introducer needles not only determines puncture efficiency and patient comfort, but also impacts production cost and consistency.

[0003] At present, the manufacturing of traditional guide needles usually adopts the grinding process to achieve the sharpening of the needle tip. Although this process can meet the sharpness requirements of the needle tip, the grinding process requires high-precision equipment and generates a large amount of metal debris and waste, which increases the material cost and subsequent processing costs. The processing speed of the grinding process is limited, and it is difficult to meet the needs of mass production. In addition, due to the many variables in the process (such as grinding angle, material loss, etc.), the consistency of the needle tip is difficult to fully control, affecting the reliability of product quality. The metal particles and coolant generated during the grinding process may also cause pollution to the environment, and improper handling may also affect the health of the operator. Therefore, there is an urgent need for a low-cost, high-efficiency, high-quality and environmentally friendly guide needle manufacturing process. Summary of the Invention

[0004] In order to overcome the shortcomings and deficiencies in the prior art, the object of the present invention is to provide a manufacturing process for a CGM introducer needle that is low-cost, highly efficient, high-quality and environmentally friendly.

[0005] To achieve the above object, a manufacturing process of a CGM guide needle of the present invention comprises the following steps:

[0006] S1, pretreatment: providing a stamping die, installing the stamping die on a punch press, adjusting the operating parameters of the punch press and the stamping die according to the shape and size of the required guide pin, providing a cleaned metal raw material sheet and placing it in the lower die of the stamping die;

[0007] S2, sharpening: Using the upper and lower dies of a stamping die, one end of the metal stock sheet is punched. The upper die is provided with a wedge-shaped cutting edge, and the lower die is provided with a wedge-shaped protrusion corresponding to the wedge-shaped cutting edge. The wedge-shaped cutting edge is used to punch out one end of the metal stock sheet in the positioning device, and the metal stock sheet located outside the wedge-shaped protrusion is punched out, so that a sharp needle tip portion is formed on one end of the metal stock sheet.

[0008] S3, chamfering: using the first trimming punch of the upper die of the stamping die to punch out one end of the metal raw material sheet near the cutting edge, so that two chamfered portions are formed on both sides of the end of the metal raw material sheet near the cutting edge. Simultaneously, using the second trimming punch of the upper die to punch out the metal raw material sheet to form a blank;

[0009] S4, forming: using the left and right dies of a stamping die to press the left and right sides of the metal raw material sheet processed in step S3, so that the left and right sides of the metal raw material sheet are folded toward each other to form two bent portions, and a needle groove for accommodating the sensing electrode of the external glucose sensor is formed between the two bent portions. The metal raw material sheet with the needle tip, the chamfered portion, and the needle groove is the guide needle;

[0010] S5, post-processing: the guide needle processed in step S4 is removed from the stamping die by using the stripping die of the stamping die. The removed guide needle undergoes surface treatment and then enters the next process.

[0011] Furthermore, the needle tip portion is located at one end of the blank, and the blank has a main body portion and a first side portion and a second side portion located on both sides of the main body portion. The needle tip portion is located at one end of the main body portion, and the two chamfered portions are respectively located at one end of the first side portion and the second side portion close to the needle tip portion. The first side portion and the second side portion are folded close to each other under the extrusion of the left and right dies of the stamping die to form the two bent portions, and the two bent portions and the main body portion enclose each other to form the needle groove.

[0012] Furthermore, the pretreatment step also includes a punching step. Two positioning holes are provided on the lower die, and a runway-shaped punch is provided on the upper die to cooperate with the positioning holes. When the metal raw material sheet is positioned by the positioning device, the runway-shaped punch is first aligned with the positioning holes to punch out two limiting holes at the top of the metal raw material sheet.

[0013] Furthermore, the metal raw material sheet is made of stainless steel with a hardness of 350 HV or above or titanium alloy with a hardness of 400 or above.

[0014] Furthermore, the manufacturing process of the CGM guide needle also includes a punching step, which is carried out simultaneously with the chamfering step. The punching step includes using the second trimming punch on the upper die of the stamping die to punch out two arc-shaped snap-in grooves on both sides of the end of the metal raw material sheet away from the needle head. The snap-in grooves are used to connect the guide needle and the needle pushing device of an external glucose monitor.

[0015] Furthermore, the second trimming punch (the second trimming punch and the first trimming punch are of an integrated structure) punches out four limiting protrusions on the end of the metal raw material sheet away from the needle head while punching the clamping groove (that is, three grooves are punched out on both sides of the end of the metal raw material sheet away from the needle head respectively). The four limiting protrusions are divided into two groups and are symmetrically distributed along the symmetry axis of the guide needle.

[0016] Furthermore, the angle between the edge of the needle tip and the length direction of the metal raw material sheet is 15°-30°.

[0017] Furthermore, the thickness of the metal raw material sheet is 0.05-0.15 mm.

[0018] Furthermore, the two chamfered portions are located at one end of the two bending portions close to the needle tip, and the cross-sectional area of ​​the chamfered portions gradually increases from the end of the guide needle close to the needle tip to the end of the guide needle away from the needle tip.

[0019] Furthermore, the needle groove is arranged in a "U" shape.

[0020] Furthermore, the upper die is mounted on the hydraulic output end of the punch press via a rectangular upper die base, and the lower die is mounted on the base of the punch press via a lower die base made of the same material and shape as the upper die base.

[0021] Furthermore, the post-processing step includes plating a modified coating on the outer surface of the guide needle, and the material of the modified coating is one or more combinations of titanium nitride, titanium carbonitride, chromium aluminum nitride, aluminum titanium nitride, and zirconium dioxide.

[0022] Furthermore, the outer surface of the modified coating is coated with a lubricating coating, and the material of the lubricating coating is parylene or PTFE.

[0023] Furthermore, the thickness of the modified coating is 1-8 μm, and the thickness of the lubricating coating is 0.25-3 μm.

[0024] Furthermore, the post-processing step further comprises the following steps:

[0025] (a) Deburring: Use chemical agents to soak the guide pin after it is cut from the stamping die to remove the burrs by chemical reaction, or use a roller deburring machine or polishing machine to mechanically polish the edge of the guide pin;

[0026] (b) Surface cleaning: The guide pin after being cut from the stamping die is placed in the cleaning fluid in an ultrasonic cleaner. The high-frequency vibration ultrasonic waves generated by the ultrasonic cleaner generate tiny bubbles in the cleaning fluid to remove oil and impurities on the surface of the guide pin;

[0027] (c) Heat treatment: The cleaned guide needle is heated to a preset temperature and sequentially annealed, quenched, and tempered before entering the next process;

[0028] (d) Inspection: Use a precision caliper or a three-dimensional coordinate measuring machine to check the size and shape parameters of the guide needle to ensure that the dimensions of the needle tip, main body, and bend meet the design requirements;

[0029] (e) Sterilization packaging: Use high-temperature steam equipment to heat the guide needle so that the high-temperature steam kills the bacteria and microorganisms attached to the surface of the guide needle, or use gamma rays or electron beams to irradiate and sterilize the guide needle. The sterilized guide needle is packaged in a sterile bag or sterile box and then enters the next process.

[0030] Furthermore, after the heat treatment step, the guide needle is cleaned again using an ultrasonic cleaner, and then the modified coating is plated. After the modified coating and the lubricating coating are set, the detection step is performed.

[0031] The manufacturing process for a CGM introducer needle employs stamping and die technology to process a high-hardness metal sheet into an introducer needle with a needle tip, chamfer, and groove. Specifically, a punch press and die are used to stamp, cut, and bend the metal sheet to form the desired introducer needle shape. Subsequently, a series of post-processing steps, including deburring, surface cleaning, heat treatment, and surface coating, enhance the surface quality, mechanical properties, and biocompatibility of the introducer needle.

[0032] The present invention has the following beneficial effects: This manufacturing process enables high-precision and high-efficiency manufacturing of guide needles, ensuring product quality and consistency. A multi-step post-processing process improves the guide needle's surface finish and corrosion resistance, enhancing its suitability for use in medical settings. Furthermore, the superior material selection and sophisticated processing techniques ensure that the guide needle possesses excellent mechanical properties and biocompatibility, meeting the stringent requirements of continuous glucose monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Schematic diagram of the manufacturing process of the CGM guide needle of the present invention;

[0034] Figure 2 A front view of a CGM introducer needle manufactured using the manufacturing process of the present invention;

[0035] Figure 3 A side view of a CGM introducer needle manufactured using the manufacturing process of the present invention;

[0036] Figure 4 A top view of an upper die of a stamping die used in the manufacturing process of the present invention;

[0037] Figure 5 A top view of a lower die of a stamping die used in the manufacturing process of the present invention;

[0038] Figure 6 It is a front view of the stamping die used in the manufacturing process of the present invention.

[0039] The accompanying drawings include: 1. stamping die; 2. guide needle; 11. upper die; 111. wedge-shaped cutting edge; 112. first trimming punch; 113. second trimming punch; 12. lower die; 13. left die; 14. right die; 21. needle tip; 22. chamfered portion; 23. bending portion; 24. needle groove; 25. snap-fit ​​groove; 26. limiting protrusion; 27. mounting portion; 3. upper die base; 4. lower die base; 5. stripping die. DETAILED DESCRIPTION

[0040] In order to facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments and drawings. The contents mentioned in the embodiments are not intended to limit the present invention.

[0041] See also Figure 1 Figure 6 As shown, the manufacturing process of a CGM guide needle provided by the present invention mainly includes the steps of pre-processing the metal raw material sheet, punching, sharpening, chamfering, forming, notching, and post-processing. Through a multi-stage stamping die 1 and surface treatment process, a guide needle 2 that meets high precision and high performance requirements is manufactured. The needle tip 21 is used for puncturing the skin, the needle groove 24 is used to accommodate the sensor electrode, and the chamfered portion 22 and the clamping groove 25 facilitate the installation of the needle push device and the function of the guide needle 2. The manufacturing process mainly includes the following steps:

[0042] Step S1, pretreatment: provide a titanium alloy metal raw material sheet with a thickness of 0.1mm and a hardness of 400HV, chemically clean it to remove surface impurities, and dry it for use. Install the stamping die 1 on the punch press, and the die includes an upper die 11 and a lower die 12 that are relatively movable, and a left die 13 and a right die 14 that are relatively movable on the lower die 12. Subsequently, adjust the operating parameters of the punch press so that the mold opening and closing spacing and the punching force meet the processing requirements of the metal raw material sheet. Place the cleaned metal raw material sheet in the mold positioning device and fix it with a pneumatic clamp. The metal raw material sheet is in a straight rectangular shape. After being placed in the mold positioning device, the metal raw material sheet is transferred from one end of the stamping die 1 to the other end via an external feeding mechanism to cooperate with the stamping and bending actions of the upper die 11, the lower die 12, the left die 13 and the right die 14.

[0043] Step S2, sharpening: The wedge-shaped cutting edge 111 of the upper die 11 of the stamping die 1 is pressed downwardly into one end of the metal stock sheet. The metal stock sheet is then pressed into the wedge-shaped protrusion of the lower die 12. Excess material is cut from the edge of the wedge-shaped protrusion into a pre-set waste groove within the die. A sharp needle tip 21 is formed on the wedge-shaped protrusion at one end of the metal stock sheet. The angle between the edge of this needle tip 21 and the length of the metal stock sheet is 15°. This angle reduces the penetration resistance of the guide needle 2 when piercing the skin, facilitating the subsequent implantation of the sensor electrode.

[0044] Step S3, chamfering: After the needle tip 21 is formed, the first trimming punches 112 (two in number) of the upper die 11 of the stamping die 1 are used to punch out the end of the metal raw material sheet close to the needle tip 21, so that two chamfered portions 22 are formed on both sides of the metal raw material sheet. The chamfering angle of the chamfered portions 22 is 22°, and the cross-sectional area of ​​the chamfered portions 22 gradually increases from the needle tip outward. This structural design optimizes the mechanical properties of the needle tip and reduces damage to the skin.

[0045] Step S4, forming: After the chamfered metal sheet is extruded through the left and right dies 13 and 14, the two sides of the metal sheet are folded toward the center, forming two bent portions 23. (The stamping surface of the upper die 11 has two symmetrical raised structures, and the pressure-bearing surface of the lower die 12 has two concave pressing surfaces corresponding to the raised structures. The shape and size of the two raised structures correspond to the pre-creases required on both sides of the main body. The edges of the raised structures are rounded to prevent scratching the metal sheet during the stamping process. The pre-creases create a stress concentration area on the metal sheet, making subsequent bending easier along the predetermined direction and avoiding irregular deformation or misalignment during bending.) These two bent portions 23 and the main body together form a "U"-shaped needle groove 24, which is used to accommodate the sensing electrode of the glucose sensor. During use, after the needle pusher inserts the guide needle 2 into human skin tissue, the sensing electrode is guided by the guide needle 2 to the subcutaneous tissue, and the needle pusher can then retract the guide needle 2.

[0046] The manufacturing process of the CGM guide needle also includes a notching step, which is carried out simultaneously with the chamfering step. The notching step is to use the second trimming punch 113 of the stamping die 1 to punch out two arc-shaped snap-in grooves 25 on both sides of the distal end of the needle tip 21. The snap-in grooves 25 are used to connect with an external needle-pushing device to ensure stable installation of the guide needle 2 and the launching end of the needle-pushing device.

[0047] Step S5, post-processing:

[0048] (a) Deburring: Soak the guide needle 2 in a chemical agent to remove surface burrs; or place the guide needle 2 in a roller deburring machine for mechanical grinding. The chemical agent formula is: 2-5% hydrofluoric acid, 15-25% nitric acid, and the balance water. The soaking time is 10-20 minutes, and the temperature is room temperature. In this embodiment, the guide needle 2, after being soaked in the chemical agent, is cleaned and placed in the roller deburring machine with the selected grinding medium (ceramic abrasive), and an appropriate amount of water or lubricating fluid is added. Alternatively, the guide needle 2 is placed in the reaction chamber of a plasma device, evacuated, and then an inert gas is introduced. The plasma generator is started, and the burrs on the guide needle surface are stripped and ablated using high-energy plasma. After processing is completed, the surface of the guide needle 2 is cleaned to remove residual gas adsorbents. After checking that the surface of the guide needle 2 is undamaged, proceed to the next step.

[0049] (b) Surface Cleaning: The deburred guide needle 2 is placed in a cleaning solution in a cleaning tank within an ultrasonic cleaning apparatus, and ultrasonic vibration is used to remove residual impurities and oil stains on the surface of the guide needle 2. The cleaning solution is deionized water.

[0050] (c) Heat treatment: First, the cleaned guide needle 2 is placed in a high-temperature furnace, heated to 700°C and maintained for a period of time for annealing treatment to eliminate internal stress and soften the guide needle 2; then, the guide needle 2 is quickly taken out of the high-temperature furnace and immersed or sprayed with a cooling medium (such as oil or water) and quickly cooled to 200°C for quenching treatment to improve the hardness and strength of the material; finally, the quenched guide needle 2 is placed in a heating furnace again, heated to 500°C and maintained for a period of time for tempering treatment to reduce the brittleness caused by quenching and further optimize the toughness and plasticity of the material.

[0051] (d) Surface coating: First, a titanium nitride (TiN) coating is applied. The specific method is to place the guide needle 2 that has undergone pretreatment (such as cleaning and activation) in a vacuum coating device. Through physical vapor deposition (PVD) or chemical vapor deposition (CVD) techniques, a 5-μm-thick TiN coating is formed on the surface of the guide needle 2. This coating has the characteristics of high hardness, wear resistance, and good biocompatibility. Subsequently, on top of the TiN coating, vapor phase deposition (VPD) technology is used to vaporize and deposit parylene monomer on the surface of the guide needle 2 under vacuum conditions, forming a 1-μm-thick parylene lubricating coating. This coating has excellent lubricity and bioinertness, which can further improve the puncture performance of the guide needle 2 and reduce tissue damage.

[0052] (e) Inspection and sterilization: To ensure the quality and safety of the guide needles 2, it is first necessary to use a precision caliper to accurately measure the needle tip angle and the depth of the needle groove 24 of each guide needle 2 to ensure that it meets the design specifications and quality standards; then, the guide needles 2 that have passed the measurement are placed in a gamma ray sterilization device and sterilized according to the preset dosage and time to completely kill any possible microorganisms and ensure that the product reaches a sterile state; finally, the sterilized guide needles 2 are individually packaged in a sterile bag under a sterile environment and sealed to prevent secondary contamination, thereby ensuring the sterility of the product during transportation and use.

[0053] In the present invention, the stamping die is a multifunctional composite die. During implementation, a wedge-shaped cutting edge, under the action of the upper die, punches one end of the metal sheet, collaborating with the wedge-shaped protrusion of the lower die to form the needle tip. The metal sheet then advances slightly to enter the chamfering and notching steps, which are performed simultaneously. The first trimming punch punches the end closest to the needle tip, forming two chamfers. Simultaneously, the second trimming punch punches an arcuate snap-in groove and a retaining protrusion at the end of the metal sheet away from the needle tip, and also punches the center of the metal sheet to form a blank with the initial shape of a guide needle. The metal sheet then advances further to the forming step. The coordinated extrusion of the left and right dies folds the left and right sides, forming a bend and a needle groove. The guide needle then enters the stripping step. After forming, the guide needle is removed from the die using a stripping device to avoid damage to the needle tip and coating. By integrating multiple process steps, the number of mold changes is reduced, production efficiency and processing accuracy are improved, and equipment costs and energy consumption are reduced, making guide needle manufacturing more environmentally friendly and efficient.

[0054] Specifically, the forming process of the guide needle 2 begins with a 0.1mm thick sheet of metal stock. After a pre-cutting step in the stamping die 1, the sheet is formed into a 0.1mm thick, 20mm long, and 1.5mm wide sheet. This sheet consists of a central main body, flanked by first and second side portions. In the punching die, one end of the main body is machined into a sharp needle tip 21. Simultaneously, the first and second side portions, near the needle tip 21, are each formed with a chamfer 22 by a first trimming punch. Subsequently, under the pressure of the left and right dies 13 and 14 of the stamping die 1, the first and second side portions gradually converge toward the centerline of the main body and bend, ultimately folding to form two bent portions 23. These two bent portions 23, together with the main body, enclose a needle groove 24 of a specific depth (0.5mm) and shape (a rectangular opening). This needle groove 24 structure is crucial for the guiding and puncture functions of the guide needle 2. The entire forming process transforms a planar metal raw material sheet into a guide needle 2 with a three-dimensional structure and specific functions through precise extrusion and bending of the stamping die 1 .

[0055] Specifically, the metal raw material sheet in the present invention is made of Ti-6Al-4V, but other titanium alloys with a hardness of 400 HV or higher can also be used. Titanium alloys offer superior biocompatibility and reduced weight, while also possessing higher strength and fatigue resistance, further enhancing the performance of the guide needle 2. In actual production, stainless steel with a hardness of 350 HV (Vickers hardness) or higher, such as 304, 316, or 17-4PH stainless steel, can be selected. These materials offer excellent corrosion resistance and biocompatibility, as well as high strength and toughness to meet the mechanical requirements of the guide needle 2 during puncture and guidance.

[0056] The metal sheet made of Ti-6Al-4V in this embodiment ensures that the guide needle 2 is not easily deformed or broken during the puncture process, thereby ensuring the success rate and safety of the puncture and increasing the service life of the guide needle 2. In addition, the high hardness material helps maintain the sharpness of the needle tip, reduces puncture resistance, and reduces pain for the patient.

[0057] During the manufacturing process of the guide needle 2, in order to achieve a reliable connection between it and the external glucose monitor's push-needle device, a punching step is required after the chamfering step and before the forming step. Specifically, the upper die 11 of the stamping die is used, and the upper die 11 is equipped with two second trimming punches 113, and the two punches are respectively located on both sides of the end of the metal raw material sheet away from the needle tip 21. During the stamping process, the two second trimming punches 113 will punch out two arc-shaped snap-fit ​​grooves 25 and two limiting protrusions 26 on the metal raw material sheet. The metal raw material sheet above the snap-fit ​​groove 25 is the mounting portion 27 of the guide needle 2, and the mounting portion 27 is roughly rectangular. The position and shape of the two snap-fit ​​grooves 25 are designed to be arc-shaped, and can be precisely connected with the snap-fit ​​structure on the mounting portion 27 and the push-needle device of the glucose monitor with the help of the mounting portion 27.

[0058] This snap-fitting method allows the guide needle 2 to be securely fixed to the needle pusher, ensuring stability and reliability during the puncture process while facilitating installation and replacement of the guide needle 2. Furthermore, the punched snap-fitting groove 25 structure offers greater strength and durability than other connection methods, effectively preventing the guide needle 2 from loosening or falling off during use, thereby improving safety.

[0059] In order to ensure that the guide needle 2 has good puncture performance and reduce tissue damage, the angle between the edge of the needle tip 21 and the length direction of the metal raw material sheet is precisely controlled to be between 15° and 30°. In specific implementation, in the stamping die 1, by designing the opening angle of the wedge-shaped cutting edge 111 of the upper die 11 of the stamping die 1, the edge of the needle tip 21 forms a predetermined angle with the length direction of the metal raw material sheet. The formation of this angle is completed at the same time as the metal raw material sheet is stamped to form the needle tip 21. The wedge-shaped cutting edge 111 of the die will cut and plastically deform the metal raw material sheet at a preset angle of 15° to 30°, thereby forming a sharp needle tip. By controlling the cutting angle and depth of the stamping die 1, the edge angle of the needle tip 21 can be precisely controlled.

[0060] The angle range of 15° to 30° is selected to achieve the best balance during the puncture process. An angle that is too small will result in an overly sharp needle tip, which can easily cause tissue cutting and damage, while an angle that is too large will increase puncture resistance and make puncture difficult. The angle range of 15° to 30° ensures the sharpness of the needle tip while reducing puncture resistance, thereby achieving efficient and low-damage puncture. Optimizing this angle range can improve the puncture performance of the guide needle 2, reduce the patient's pain, and increase the success rate of puncture.

[0061] In order to ensure that the guide needle 2 can be smoothly bent during the forming process and to reduce stress concentration at the bend portion 23, the two chamfered portions 22 are designed to be located at one end of the two bend portions 23 close to the needle tip portion 21, and their cross-sectional areas gradually increase from the end of the guide needle 2 close to the needle tip portion 21 to the end of the guide needle 2 away from the needle tip portion 21. In specific implementation, during the stamping or cutting process of the metal raw material sheet, the precise design of the mold is utilized to form chamfers with gradually increasing cross-sectional areas at the ends of the first and second side portions close to the needle tip portion 21. This chamfering can be achieved by the special shape of the cutting edge or stamping protrusion of the mold (for example, after the chamfering process, the stamping protrusion can be used to squeeze the chamfer so that its cross-sectional area gradually increases from the needle tip portion 21 toward the snap-in groove 25).

[0062] After the chamfer is formed, when the first and second side portions are bent under the pressure of the mold, the cross-sectional area of ​​the chamfered portion 22 gradually increases, and the bending force can be more evenly distributed in the chamfered portion 22, rather than being concentrated at the starting point of the bend. This design can effectively reduce stress concentration at the bend portion 23, preventing the metal raw material from breaking or deforming during the bending process, thereby improving the success rate of bending and the yield rate of the product. In addition, the gradually increasing chamfer can further reduce the resistance of the two bends 23 when entering the human skin, making it easier for the guide needle 2 to pierce the skin and implant the sensing electrode into the human subcutaneous tissue.

[0063] To further enhance the adaptability of the guide needle 2, a post-processing step is performed after all molding steps are completed. This involves depositing a modified coating on the outer surface of the guide needle 2. In this embodiment, physical vapor deposition (PVD) technology is used to deposit a selected modified coating material on the outer surface of the guide needle 2. These coating materials include, but are not limited to, titanium nitride (TiN), titanium carbide nitride (TiCN), aluminum chromium nitride (CrAlN), aluminum titanium nitride (AlTiN), and zirconium dioxide (ZrO2), or a combination of one or more of these materials.

[0064] For example, a layer of titanium nitride can be first plated as a base layer, and then a layer of titanium nitride carbide can be plated as a surface layer to obtain better performance. The coating process requires precise control of parameters such as temperature, pressure, and gas flow to ensure that the coating has good uniformity, adhesion, and density. These specific materials are selected as modified coatings because they have excellent hardness, wear resistance, corrosion resistance, and biocompatibility. Titanium nitride and titanium nitride carbide have extremely high hardness, which can effectively improve the wear resistance of the surface of the guide needle 2, reduce friction during the puncture process, and make the puncture smoother. Chromium aluminum nitride and titanium aluminum nitride have excellent high temperature resistance and oxidation resistance, which can improve the durability of the guide needle 2. Zirconium dioxide has good biocompatibility, which can reduce the interaction between the guide needle 2 and human tissue and reduce the risk of inflammatory response. By plating these modified coatings, the overall performance of the guide needle 2 can be significantly improved, its service life can be extended, and the safety and comfort of puncture can be improved.

[0065] To further reduce friction during puncture on the guide needle 2 and improve the smoothness and comfort of the puncture, after applying the modified coating, in this embodiment, a lubricating coating is applied to the surface of the modified coating. In this embodiment, parylene is uniformly applied to the surface of the modified coating using a vapor deposition method. Parylene is a high molecular weight polymer with excellent biocompatibility, chemical inertness, and a low coefficient of friction. In actual production, the lubricating coating can be made of polytetrafluoroethylene (PTFE). PTFE, commonly known as Teflon, also has an extremely low coefficient of friction and good chemical resistance. It can be applied to the surface of the guide needle 2 by spraying or dipping.

[0066] To ensure the effectiveness and stability of the lubricating coating, the thickness of the lubricating coating is precisely controlled between 0.25 microns and 3 microns. A coating that is too thin will result in poor lubrication, while a coating that is too thick may affect the dimensional accuracy of the guide needle 2 or increase the risk of the coating falling off. At the same time, to ensure that the modified coating performs its due performance, the thickness of the modified coating is controlled between 1 micron and 8 microns. A modified coating that is too thin may not provide sufficient hardness and wear resistance, while a coating that is too thick may affect the flexibility and dimensional accuracy of the guide needle 2.

[0067] By coating the modified coating with a lubricating coating and precisely controlling the thickness of both coatings, the friction and resistance of the guide needle 2 during puncture can be significantly reduced, thereby improving the smoothness and accuracy of the puncture and reducing pain for the patient. Furthermore, the lubricating coating further enhances the biocompatibility of the guide needle 2, reducing the risk of tissue damage and inflammatory reactions.

[0068] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there may be changes in the specific implementation methods and application scopes. The contents of this specification should not be understood as limiting the present invention.

Claims

1. A manufacturing process for a CGM guide needle, characterized in that: The following steps are involved: S1, pretreatment: providing a stamping die (1), installing the stamping die (1) on a punching machine, adjusting the operating parameters of the punching machine and the stamping die (1) according to the shape and size of the required guide needle (2), providing a cleaned metal raw material sheet and placing it in the lower die (12) of the stamping die (1); S2, sharpening: punching one end of the metal raw material sheet using the upper die (11) and the lower die (12) of the punching die (1), wherein the upper die (11) is provided with a wedge-shaped cutting edge (111), and the lower die (12) is provided with a wedge-shaped protrusion corresponding to the wedge-shaped cutting edge (111), punching one end of the metal raw material sheet in the lower die (12) using the wedge-shaped cutting edge (111), punching out the metal raw material sheet located outside the wedge-shaped protrusion, so that a sharp needle tip portion (21) is formed at one end of the metal raw material sheet; S3, chamfering: using a first trimming punch (112) of an upper die (11) of a stamping die (1) to punch out one end of a metal raw material sheet close to the needle tip portion (21), so that two chamfered portions (22) are formed on both sides of the metal raw material sheet close to the needle tip portion (21), and simultaneously using a second trimming punch (113) of the upper die (11) to punch out the metal raw material sheet to form a blank; the needle tip portion (21) is located at one end of the blank, the blank having a main body portion and a first side portion and a second side portion located on both sides of the main body portion, and the two chamfered portions (22) are respectively located at one end of the first side portion and the second side portion close to the needle tip portion (21); S4, forming: the punching surface of the upper die (11) has two symmetrical convex structures, the pressure-bearing surface of the lower die (12) is concavely provided with two concave pressure surfaces corresponding to the convex structures, the shapes and sizes of the two convexities correspond to the pre-folds to be formed on both sides of the main body, the edges of the convexities are provided with rounded corners, the left die and the right die (14) are relatively movable and arranged on the lower die (12); the symmetrical convexities provided on the upper die (11) are used to punch a pre-fold in the middle of the blank, and the left die (13) and the right die (14) of the punching die (1) are used to extrude the two sides of the pre-fold of the blank away from each other, so that The left and right sides of the blank are folded toward each other to form two bent portions (23), and a needle groove (24) for accommodating a sensing electrode of an external glucose sensor is formed between the two bent portions (23). The metal raw material sheet having the needle tip portion (21), the chamfered portion (22) and the needle groove (24) is the guide needle (2); the first side portion and the second side portion are folded toward each other under the extrusion of the left die (13) and the right die (14) of the stamping die (1) to form the two bent portions (23), and the two bent portions (23) and the main body portion enclose the needle groove (24); S5, post-processing: using the stripping die (5) of the stamping die (1) to remove the guide needle (2) processed in step S4 from the stamping die (1).

2. The manufacturing process of the CGM guide needle according to claim 1, characterized in that: The metal raw material sheet is made of stainless steel with a hardness of 350 HV or above or titanium alloy with a hardness of 400 HV or above.

3. The manufacturing process of the CGM guide needle according to claim 1, characterized in that: The manufacturing process of the CGM guide needle further includes a notching step, which is performed simultaneously with the chamfering step. The notching step includes using a second trimming punch (113) on the upper die (11) of the stamping die (1) to punch out two arc-shaped snap-in grooves (25) on both sides of an end of the blank away from the needle tip (21). The snap-in grooves (25) are used to install the guide needle (2) to a needle push device of an external glucose monitor.

4. The manufacturing process of the CGM guide needle according to claim 1, characterized in that: The angle between the cutting edge of the needle tip (21) and the length direction of the blank is 5°-60°.

5. The manufacturing process of the CGM guide needle according to claim 1, characterized in that: The thickness of the metal raw material sheet is 0.05-0.15 mm.

6. The manufacturing process of the CGM guide needle according to claim 1, characterized in that: The two chamfered portions (22) are located at one end of the two bent portions (23) close to the needle tip portion (21), and the cross-sectional area of ​​the chamfered portion (22) gradually increases from the end of the guide needle (2) close to the needle tip portion (21) to the end of the guide needle (2) away from the needle tip portion (21).

7. The manufacturing process of the CGM guide needle according to claim 1, characterized in that: The post-processing step includes plating a modified coating on the outer surface of the guide needle (2), wherein the material of the modified coating is one or more combinations of titanium nitride, titanium carbonitride, chromium aluminum nitride, aluminum titanium nitride, and zirconium dioxide.

8. The manufacturing process of the CGM guide needle according to claim 7, characterized in that: The outer surface of the modified coating is covered with a lubricating coating, and the material of the lubricating coating is parylene or PTFE.

9. The manufacturing process of the CGM guide needle according to claim 1, characterized in that: The post-processing step further comprises the following steps: (a) Deburring: soaking the guide needle (2) after being cut from the stamping die (1) in a chemical agent to remove the burrs on the surface of the guide needle (2) by chemical reaction, or mechanically grinding the edge of the guide needle (2) using a roller deburring machine or a polishing machine, or deburring the guide needle (2) using a low-temperature plasma generator; (b) Surface cleaning: placing the deburred guide needle (2) into a cleaning solution in an ultrasonic cleaning apparatus, and using the high-frequency vibration ultrasonic waves generated by the ultrasonic cleaning apparatus to generate tiny bubbles in the cleaning solution to remove oil stains and impurities on the surface of the guide needle (2); (c) Heat treatment: The cleaned guide needle (2) is heated to a preset temperature and sequentially subjected to annealing, quenching, and tempering before entering the next process: (d) Inspection: Use a precision caliper or a three-dimensional coordinate measuring machine to check the size and shape parameters of the guide needle (2) to ensure that the dimensions of the needle tip (21), the main body, and the bending portion (23) meet the design requirements; (e) Sterilization packaging: using a high-temperature steam device to heat the guide needle (2) so that the high-temperature steam kills the bacteria and microorganisms attached to the surface of the guide needle (2), or using gamma rays or electron beams to perform radiation sterilization on the guide needle (2). The sterilized guide needle (2) is packaged in a sterile bag or sterile box and then enters the next process.

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