Manufacturing process of CGM guide needle

Abstract

The invention relates to the technical field of surgical instruments, and particularly discloses a manufacturing process of a CGM guide needle, which comprises the following steps: S1, mounting a stamping die on a punching machine, adjusting parameters, and fixing a cleaned metal raw material sheet in a lower die positioning device; s2, a wedge-shaped cutting edge of the upper die is matched with a wedge-shaped protrusion of the lower die, one end of the metal raw material sheet is punched, and a sharp needle point part is formed; s3, punching one end, close to the needle tip, of the metal raw material sheet by using a first trimming punch, and forming chamfer parts on two sides; s4, stamping the middle part of the metal raw material sheet by utilizing the symmetrical bulges of the upper die to form a pre-folding mark, and extruding two sides of the pre-folding mark by utilizing the left and right dies, so that the metal raw material sheet is folded to form two bent parts, a needle groove is formed between the two bent parts, and the guide needle with a needle tip part, a chamfer part and the needle groove is obtained; and S5, the formed guide needle is taken out of the mold through a stripping mold, and the guide needle enters the next procedure after being subjected to surface treatment.

Description

Technical Field

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

[0002] As a key component, the CGM (Continuous Glucose Monitoring) guide needle is directly used to puncture the human skin to implant the sensor. The manufacturing process of the guide needle not only determines its puncture efficiency and patient comfort, but also affects the cost and consistency of production.

[0003] At present, the manufacturing of traditional guide needles usually adopts a 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 presence of 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, an object of the present invention is to provide a manufacturing process for a CGM introducer needle with low cost, high efficiency, high quality and good environmental friendliness.

[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 needle, providing a cleaned metal raw material sheet and placing it in the lower die of the stamping die;

[0007] S2, sharpening: punching one end of the metal raw material sheet by using the upper die and the lower die of the punching die, wherein 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, punching one end of the metal raw material sheet in the positioning device by using the wedge-shaped cutting edge, punching out the metal raw material sheet located outside the wedge-shaped protrusion, so that one end of the metal raw material sheet forms a sharp needle tip;

[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 close to the cutting edge, so that two chamfered portions are formed on both sides of the end of the metal raw material sheet close to the cutting edge, and at the same time 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 a left die and a right die 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 in a direction close to each other to form two bent parts, and a needle groove for accommodating a sensing electrode of an external glucose sensor is formed between the two bent parts. The metal raw material sheet having the needle tip, the chamfered part 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 enters the next process after surface treatment.

[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, in which two positioning holes are provided on the lower die, and a runway-shaped punch cooperating with the positioning holes is provided on the upper die. 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 a 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 out the snap-fitting groove (i.e., 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 portion, and the cross-sectional area of ​​the chamfered portions gradually increases from the end of the guide needle close to the needle tip portion to the end of the guide needle away from the needle tip portion.

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

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

[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 nitride carbide, 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 needle 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 grind the edge of the guide needle;

[0026] (b) Surface cleaning: Place the guide needle after being cut from the stamping die into the cleaning liquid in the ultrasonic cleaner, and use the high-frequency vibration ultrasonic waves generated by the ultrasonic cleaner to generate tiny bubbles in the cleaning liquid to remove oil and impurities on the surface of the guide needle;

[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 bending part 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 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 of a CGM guide needle of the present invention uses stamping and die technology to process a high-hardness metal raw material sheet into a guide needle with a needle tip, a chamfered portion and a needle groove. Specifically, a punch press and a stamping die are used to stamp, cut and bend the metal raw material sheet to form the desired shape of the guide needle. Subsequently, a series of post-processing steps such as deburring, surface cleaning, heat treatment and surface coating treatment are performed to improve the surface quality, mechanical properties and biocompatibility of the guide needle.

[0032] Beneficial effects of the invention: The manufacturing process achieves high-precision and high-efficiency manufacturing of the guide needle, ensuring the quality and consistency of the product. The multi-step post-processing process improves the surface finish and corrosion resistance of the guide needle, enhancing its applicability in medical environments. In addition, the excellent material selection and sophisticated processing technology enable the guide needle to have good mechanical properties and biocompatibility, meeting the strict requirements of continuous glucose monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the manufacturing process of the CGM guide needle of the present invention;

[0034] Figure 2 A front view of a CGM guide 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] Reference numerals include:

[0040] 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. Chamfering part; 23. Bending part; 24. Needle groove; 25. Snap-fit ​​groove; 26. Limiting protrusion; 27. Mounting part; 3. Upper die seat; 4. Lower die seat; 5. Stripping die. DETAILED DESCRIPTION

[0041] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments and drawings. The contents mentioned in the implementation modes are not intended to limit the present invention.

[0042] 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-treatment, punching, sharpening, chamfering, forming, notching, post-treatment, etc. of the metal raw material sheet. Through the multi-stage stamping die 1 and the surface treatment process, the guide needle 2 that meets the requirements of high precision and high performance is manufactured, the needle tip 21 is used to puncture 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 pushing device and the function of the guide needle 2. The manufacturing process mainly includes the following steps:

[0043] 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 standby use. Install the stamping die 1 on the punch press, and the die includes an upper die 11, a lower die 12, and a left die 13 and a right die 14 that are relatively movable and arranged at 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 by 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.

[0044] Step S2, sharpening: The wedge-shaped cutting edge 111 of the upper die 11 of the stamping die 1 is pressed downward into one end of the metal raw material sheet, and the metal raw material sheet is pressed into the wedge-shaped protrusion of the lower die 12. The excess material is cut from the edge of the wedge-shaped protrusion to the waste groove preset in the die, and one end of the metal raw material sheet forms a sharp needle tip 21 on the wedge-shaped protrusion. The angle between the edge of the needle tip 21 and the length direction of the metal raw material sheet is 15°. The design of this angle reduces the puncture resistance of the guide needle 2 when piercing the skin, so as to facilitate the subsequent implantation of the sensor electrode.

[0045] Step S3, chamfering: After the needle tip 21 is formed, the first trimming punch 112 (two in number) of the upper die 11 of the stamping die 1 is used to punch out one 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 portion 22 is 22°, and the cross-sectional area of ​​the chamfered portion 22 gradually increases from the needle tip to the outside. This structural design optimizes the mechanical properties of the needle and reduces damage to the skin.

[0046] Step S4, forming: After the chamfered metal raw material sheet is squeezed through the left mold 13 and the right mold 14, the two sides of the metal raw material sheet are folded toward the center to form two bending parts 23 (the stamping surface of the upper mold 11 has two symmetrical convex structures, and the pressure-bearing surface of the lower mold 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-creases that need to be formed on both sides of the main body. The edges of the convexities are provided with rounded corners to avoid scratching the metal raw material sheet during the stamping process; the pre-creases will form a stress concentration area on the metal sheet, making it easier to perform subsequent bending in a predetermined direction, avoiding irregular deformation or dislocation during bending). The two bending parts 23 and the main body together enclose a "U"-shaped needle groove 24, which is used to accommodate the sensing electrode of the glucose sensor. When in use, after the push needle device inserts the guide needle 2 into the human skin tissue, the sensing electrode is guided to the subcutaneous tissue by the guide needle 2, and the push needle device can retract the guide needle 2.

[0047] The manufacturing process of the CGM guide needle also includes a notching step, which is performed 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 for connection with an external needle-pushing device to ensure stable installation of the guide needle 2 and the launching end of the needle-pushing device.

[0048] Step S5, post-processing:

[0049] (a) Deburring: Soak the guide needle 2 in chemicals to remove surface burrs; or place the guide needle 2 in a drum deburring machine for mechanical grinding. The formula of the chemical agent 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 soaked in the chemical agent is cleaned and placed in the drum deburring machine with the selected grinding medium (ceramic abrasive), and an appropriate amount of water or lubricating fluid is added. Or place the guide needle 2 in the reaction chamber of a plasma device, evacuate the vacuum, introduce inert gas, start the plasma generator, and use high-energy plasma to peel and ablate the burrs on the surface of the guide needle. After the processing is completed, clean the surface of the guide needle 2 to remove residual gas adsorbents. After checking that the surface of the guide needle 2 is not damaged, proceed to the next process.

[0050] (b) Surface cleaning: The deburred guide needle 2 is placed in a cleaning solution in a cleaning tank in an ultrasonic cleaning instrument, 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.

[0051] (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) to quickly cool to 200°C for quenching treatment to improve the hardness and strength of the material; finally, the quenched guide needle 2 is placed in the 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.

[0052] (d) Surface coating: First, titanium nitride (TiN) coating needs to be plated. The specific method is to place the guide needle 2 that has undergone pretreatment (such as cleaning and activation) in a vacuum coating device, and form a TiN coating with a thickness of 5 μm on the surface of the guide needle 2 through physical vapor deposition (PVD) or chemical vapor deposition (CVD) and other technologies. The coating has the characteristics of high hardness, wear resistance and good biocompatibility; then, on top of the TiN coating, vapor phase deposition (VPD) technology is used to vaporize and deposit the parylene monomer on the surface of the guide needle 2 under vacuum conditions to form a parylene lubricating coating with a thickness of 1 μm. The coating has excellent lubricity and bioinertness, which can further improve the puncture performance of the guide needle 2 and reduce tissue damage.

[0053] (e) Inspection and sterilization: In order to ensure the quality and safety of the guide needle 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 needle 2 that has passed the measurement is placed in a gamma ray sterilization device and sterilized according to the preset dose and time to completely kill any microorganisms that may be present and ensure that the product reaches a sterile state; finally, the sterilized guide needle 2 is 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.

[0054] In the scheme of the present invention, the stamping die is a multifunctional composite die. In specific implementation, the wedge-shaped cutting edge punches one end of the metal sheet under the action of the upper die, and cooperates with the wedge-shaped protrusion of the lower die to complete the formation of the needle tip. After that, the metal raw material sheet moves forward a part to enter the chamfering and grooving steps, and the two steps are operated synchronously: the first trimming punch punches the end close to the needle tip to form two chamfered parts, and at the same time, the second trimming punch punches the arc-shaped clamping groove and the limiting protrusion at the end of the metal sheet away from the needle tip and punches the middle of the metal raw material sheet to form a blank with a guide needle prototype. After that, the metal raw material sheet continues to move forward to enter the forming step: the cooperation and extrusion of the left and right dies fold the left and right sides to form a bending part and a needle groove. After that, the guide needle enters the stripping step: after the guide needle is formed, it is taken out of the mold by the stripping device to avoid damaging the needle tip and the coating. By integrating multiple process steps, the number of mold changes is reduced, the production efficiency and processing accuracy are improved, and the equipment cost and energy consumption are reduced, making the guide needle manufacturing more environmentally friendly and efficient.

[0055] Specifically, the forming process of the guide needle 2 begins with a metal raw material sheet with a thickness of 0.1 mm. After the pre-cutting step of the stamping die 1, a metal raw material sheet with a thickness of 0.1 mm, a length of 20 mm, and a width of 1.5 mm is formed. The metal raw material sheet consists of a central main body and a first side portion and a second side portion on both sides. In the punching die, one end of the main body will be processed into a sharp needle tip portion 21. At the same time, the first side portion and the second side portion, one end close to the needle tip portion 21, each forms a chamfered portion 22 under the punching of the first trimming punch. Subsequently, by the extrusion of the left die 13 and the right die 14 of the stamping die 1, the first side portion and the second side portion gradually approach the center line of the main body and bend, and finally fold to form two bent portions 23. The two bent portions 23 and the main body together enclose a needle groove 24 with a specific depth (0.5 mm) and shape (rectangular opening groove). This needle groove 24 structure is crucial for the guiding and puncture functions of the guide needle 2. The entire forming process transforms the metal raw material sheet with a planar structure into a guide needle 2 with a three-dimensional structure and specific functions through precise extrusion and bending of the stamping die 1.

[0056] Specifically, the metal raw material sheet in the solution of the present invention is made of Ti-6Al-4V, and other titanium alloy materials with a hardness of 400HV or more can also be selected. Titanium alloy has better biocompatibility and lighter weight, and has higher strength and fatigue resistance, which can further improve the performance of the guide needle 2. In actual production, stainless steel with a hardness of 350HV (Vickers hardness) or more can be selected, such as 304, 316 or 17-4PH stainless steel. These materials have good corrosion resistance and biocompatibility, and have high strength and toughness, which can meet the mechanical requirements of the guide needle 2 during puncture and guidance.

[0057] The metal raw material sheet made of Ti-6Al-4V in this embodiment can ensure that the guide needle 2 is not easily deformed or broken during the puncture process, ensure the success rate and safety of the puncture, and at the same time increase the service life of the guide needle 2. In addition, the high hardness material also helps to maintain the sharpness of the needle tip, reduce the puncture resistance, and reduce the pain of the patient.

[0058] In the manufacturing process of the guide needle 2, in order to achieve reliable connection between it and the external glucose monitor needle push 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-in grooves 25 and two limiting protrusions 26 on the metal raw material sheet. The metal raw material sheet above the snap-in 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-in grooves 25 are designed in an arc shape, and can be accurately connected with the snap-in structure on the mounting portion 27 and the push needle device of the glucose monitor.

[0059] Through this clamping method, the guide needle 2 can be firmly fixed on the needle pushing device, ensuring the stability and reliability of the puncture process, while facilitating the installation and replacement of the guide needle 2. In addition, the clamping groove 25 structure formed by punching has higher strength and durability than other connection methods, and can effectively prevent the guide needle 2 from loosening or falling off during use, thereby improving the safety of use.

[0060] 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 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. This angle is formed while the metal raw material sheet is stamping 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.

[0061] 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 cause the needle tip to be too sharp, which may easily lead to tissue cutting and damage, while an angle that is too large will increase the puncture resistance and cause puncture difficulties. The angle range of 15° to 30° can both ensure the sharpness of the needle tip and reduce the puncture resistance, thereby achieving efficient and low-damage puncture. The optimization of 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.

[0062] In order to ensure that the guide needle 2 can be smoothly bent during the forming process and reduce stress concentration at the bending portion 23, the two chamfered portions 22 are designed to be located at one end of the two bending 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 used to form chamfers with gradually increasing cross-sectional areas at one end of the first side portion and the second side portion close to the needle tip portion 21. This chamfer can be achieved by a 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 extrude the chamfer so that its cross-sectional area gradually increases from the needle tip portion 21 to the direction of the clamping groove 25).

[0063] After the chamfering is formed, when the first side portion and the second side portion are bent under the extrusion of the mold, the bending force can be more evenly distributed in the chamfered portion 22, rather than concentrated at the starting point of the bend, due to the gradual increase in the cross-sectional area of ​​the chamfered portion 22. This design can effectively reduce the stress concentration at the bend portion 23, avoid the metal raw material sheet 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 subcutaneous tissue of the human body.

[0064] In order to further improve the adaptability of the guide needle 2, after completing all the molding steps, a post-processing step will be performed, which includes plating a modified coating on the outer surface of the guide needle 2. In this embodiment, physical vapor deposition (PVD) technology is used to deposit the 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 nitride carbide (TiCN), chromium aluminum nitride (CrAlN), aluminum titanium nitride (AlTiN) and zirconium dioxide (ZrO2), and can also be one or more combinations of these materials.

[0065] For example, a layer of titanium nitride can be first plated as a bottom 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 puncture, and make puncture smoother. Chromium aluminum nitride and aluminum titanium 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.

[0066] In order to further reduce the friction of the guide needle 2 during the puncture process and improve the smoothness and comfort of the puncture, after the modified coating is plated, in this embodiment, a lubricating coating is coated on the outer surface of the modified coating. In this embodiment, the vapor deposition method is used to evenly cover the surface of the modified coating with parylene. Parylene is a high molecular polymer with excellent biocompatibility, chemical inertness and low friction coefficient. In actual production, the material of the lubricating coating can be polytetrafluoroethylene (PTFE). PTFE, commonly known as Teflon, also has an extremely low friction coefficient and good chemical corrosion resistance, and can be applied to the surface of the guide needle 2 by spraying or dipping.

[0067] In order to ensure the effect 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, in order 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.

[0068] By coating the modified coating with a lubricating coating and precisely controlling the thickness of the two coatings, the friction of the guide needle 2 during the puncture process can be significantly reduced, the puncture resistance can be reduced, thereby improving the smoothness and accuracy of the puncture and reducing the pain of the patient. In addition, the lubricating coating can further improve the biocompatibility of the guide needle 2 and reduce the risk of tissue damage and inflammatory response.

[0069] 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 will be changes in the specific implementation methods and application scopes. The content 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: using an upper die (11) and a lower die (12) of a stamping die (1) to stamp one end of a metal raw material sheet, the upper die (11) being provided with a wedge-shaped cutting edge (111), the lower die (12) being provided with a wedge-shaped protrusion corresponding to the wedge-shaped cutting edge (111), using the wedge-shaped cutting edge (111) to punch out one end of the metal raw material sheet in the lower die (12), punching out the metal raw material sheet located outside the wedge-shaped protrusion, so that one end of the metal raw material sheet forms a sharp needle tip portion (21); S3, chamfering: using a first trimming punch (112) of an upper die (11) of a stamping die (1) to punch out one end of the metal raw material sheet close to the cutting edge, so that two chamfered portions (22) are formed on both sides of the end of the metal raw material sheet close to the cutting edge, and at the same time using a second trimming punch (112) of the upper die (11) to punch out the metal raw material sheet to form a blank; S4, forming: using the symmetrical protrusions provided on the upper die (11) to punch a pre-fold in the middle of the blank, and using the left die (13) and the right die (14) of the punching die (1) to press 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 in a direction close to each other to form two bent parts (23), and a needle groove (24) for accommodating a sensing electrode of an external glucose sensor is formed between the two bent parts (23), and the metal raw material sheet having the needle tip part (21), the chamfered part (22) and the needle groove (24) is the guide needle (2); 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), and the guide needle (2) after being removed undergoes surface treatment and enters the next process.

2. The manufacturing process of the CGM guide needle according to claim 1, characterized in that: The needle tip portion (21) is located at one end of the blank, and the blank comprises a main body portion and a first side portion and a second side portion located on both sides of the main body portion. 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). The first side portion and the second side portion are folded close to each other under the extrusion of the left mold (13) and the right mold (14) of the stamping mold (1) to form the two bent portions (23). The two bent portions (23) and the main body portion are enclosed to form the needle groove (24).

3. 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 or above.

4. The manufacturing process of the CGM guide needle according to claim 1, characterized in that: The manufacturing process of the CGM guide needle also includes a notching step, which is performed simultaneously with the chamfering step. The notching step includes using a second trimming punch (113) on an upper die (11) of a 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 head (21), wherein the snap-in grooves (25) are used to install the guide needle (2) to a needle pushing device of an external glucose monitor.

5. 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°.

6. 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.

7. 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).

8. The manufacturing process of the CGM guide needle according to claim 1, characterized in that: The post-processing step comprises 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 carbide nitride, aluminum chromium nitride, titanium aluminum nitride, and zirconium dioxide.

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

10. The manufacturing process of the CGM guide needle according to claim 1, characterized in that: The post-processing step also includes the following steps: (a) Deburring: soaking the guide pin (2) after being cut from the stamping die (1) in a chemical agent to remove the burrs on the surface of the guide pin (2) by chemical reaction, or mechanically grinding the edge of the guide pin (2) by using a roller deburring machine or a polishing machine, or deburring the guide pin (2) by using a low-temperature plasma generator; (b) Surface cleaning: the guide needle (2) after being cut from the stamping die (1) is placed in a cleaning solution in an ultrasonic cleaning device, and high-frequency vibration ultrasonic waves generated by the ultrasonic cleaning device are used 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 step: (d) Inspection: using 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 size of the needle tip (21), the main body, and the bending part (23) meet the design requirements; (e) Sterilization packaging: The guide needle (2) is heated by a high-temperature steam device so that the high-temperature steam kills bacteria and microorganisms attached to the surface of the guide needle (2), or the guide needle (2) is irradiated and sterilized by gamma rays or electron beams. The sterilized guide needle (2) is packaged in a sterile bag or a sterile box and enters the next process.

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