A pre-pressing type fiber composite material cutting die

Abstract

The present application relates to the technical field of fiber composite material cutting, and particularly relates to a pre-pressing type fiber composite material cutting knife die, which comprises a knife seat, a cutting edge continuously extending along a product contour line in a closed ring shape, and a buffer rubber strip continuously extending along a cutting edge contour line in a closed ring shape. The buffer rubber strip is arranged on the inner side of the cutting edge, and a longitudinal section thereof comprises an upper section and a lower section. The upper section is attached to the side wall of the cutting edge, and the lower section is an inclined structure and the distance between the lower section and the side wall of the cutting edge increases in a direction away from the tip of the cutting edge. The height of the top surface of the buffer rubber strip in an initial state is higher than the tip of the cutting edge, and the height of the buffer rubber strip in a compressed state is lower than the tip of the cutting edge, and the height difference between the tip of the cutting edge and the buffer rubber strip is greater than or equal to the thickness of the material to be cut. The present application realizes pre-pressing by the segmented structure and height relationship of the buffer rubber strip, so that the buffer rubber strip contacts the material before the cutting edge during cutting, and the vertical supporting force is gradually reduced by the inclined structure of the lower section during the cutting of the cutting edge, so as to realize the yielding, thereby reducing the displacement of the material and ensuring the cutting through.

Description

Technical Field

[0001] This invention relates to the field of fiber composite material cutting technology, and specifically to a pre-compressed fiber composite material cutting die. Background Technology

[0002] Fiber composite materials are commonly used in fields such as drones to simultaneously meet the requirements of lightweighting and strength. Fiber composite materials are composed of resin layers and fiber layers. During cutting, the cutting tool needs to cut into the material from one side and penetrate its entire thickness, separating the material along a predetermined contour. During the cutting process, the material needs to be effectively compressed to prevent displacement or delamination caused by the lateral force generated by the cutting tool, while the cutting tool must be able to cut through the material smoothly.

[0003] In this scenario, the cutting process places two demands on the clamping structure: first, the material needs to be clamped before the blade contacts it to prevent displacement during the cutting process; second, the clamping structure needs to provide space for the blade as it cuts into the material so that it can cut through the material.

[0004] In existing technologies, an elastic clamping element is typically installed on the inner side of the cutting edge, utilizing the compression deformation of the elastic clamping element to provide clamping force. However, during the compression process, the clamping force of this elastic clamping element continuously increases with the amount of compression. When the tool penetrates deep into the material, the elastic clamping element still exerts a large clamping force on the material, resulting in increased cutting resistance. At the same time, after compression, the elastic clamping element is insufficient to provide enough clearance for the tool, hindering the tool from cutting through the material.

[0005] In summary, existing elastic clamping components cannot simultaneously meet the requirements of effectively clamping the material before cutting and making way for the cutting tool during the cutting process in fiber composite material cutting scenarios. Summary of the Invention

[0006] The purpose of this invention is to provide a pre-compressed fiber composite material cutting die to solve the technical problem that existing elastic clamping components are difficult to simultaneously satisfy the requirements of effectively compressing the material before cutting and making room for the cutting tool during cutting in fiber composite material cutting scenarios.

[0007] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution: This invention provides a pre-compressed fiber composite material cutting die, comprising: Knife holder; The cutting edge extends continuously along the product outline in a closed loop shape and is located at the top of the blade holder; A buffer strip extends continuously along the contour line of the blade in a closed loop shape and is disposed on the inner side of the blade. Its longitudinal section includes an upper section and a lower section that are distributed sequentially from the tip of the blade towards the blade holder. The upper section is in contact with the side wall of the blade; The lower section is an inclined structure, and the distance between the inclined structure and the blade sidewall increases in the direction away from the blade tip. The lower section is configured such that, during the compression of the buffer strip, as the angle between the lower section and the surface of the blade holder decreases, the supporting force of the lower section on the upper section in the vertical direction gradually decreases, thereby causing the equivalent vertical stiffness of the buffer strip to decrease nonlinearly with the increase of compression. The height of the top surface of the buffer strip in the initial state is the initial height, and the height in the compressed state is the compressed height; The initial height is higher than the tip of the blade, so that the buffer strip contacts the material to be cut before the blade. The compression height is lower than the tip of the blade, and the height difference between the compression height and the tip of the blade is greater than or equal to the thickness of the material to be cut, so that when the blade cuts through the material to be cut, the buffer strip has cleared the cutting path of the blade.

[0008] According to one embodiment of the present invention, the height difference between the initial height and the tip of the blade is 0.1-0.2 mm; the Shore hardness of the buffer strip is 50-60 HA.

[0009] According to one embodiment of the present invention, the inner surface of the buffer strip is provided with a plurality of strip-shaped grooves extending in a vertical direction, and the strip-shaped grooves are spaced apart circumferentially along the buffer strip.

[0010] According to one embodiment of the present invention, the cushioning strip is silicone rubber, fluororubber, or fluorosilicone rubber.

[0011] According to one embodiment of the present invention, the top surface of the buffer strip is provided with a protrusion facing the cutting direction, and the end face of the protrusion constitutes the contact surface between the buffer strip and the material to be cut; In the compressed state, the protruding end face constitutes the lowest compressed position of the buffer strip, and the protruding end face is lower than the blade tip. The height difference between the protruding end face and the blade tip is greater than or equal to the thickness of the material to be cut. The protrusion forms a clearance gap with the side of the blade near the blade edge, and the end face of the protrusion is provided with an anti-stick coating.

[0012] According to one embodiment of the present invention, the top edge of the buffer strip facing the blade side has a rounded transition.

[0013] According to one embodiment of the present invention, the angle between the outer surface of the lower section and the side wall of the blade is 10°-45°.

[0014] According to one embodiment of the present invention, the cross-section of the blade sequentially includes a circular arc at the tip of the cutting edge, a primary cutting surface, a stepped transition surface, and a secondary bevel surface; The radius of the arc at the tip of the cutting edge is 0.01-0.03 mm; The angle of the main cutting surface is 30°-45°; The stepped transition surface includes at least two steps, each step being 0.05 mm wide, and the radius of the transition fillet between the steps being 0.015 mm. The angle of the secondary slope is 15°-20°.

[0015] According to one embodiment of the present invention, the stepped transition surface includes 2-5 steps, and the height of each step gradually increases in the direction away from the tip of the cutting edge.

[0016] According to one embodiment of the present invention, the surface of the blade is provided with a ceramic coating, the thickness of the ceramic coating being 5-10 μm and the hardness being ≥HV1200.

[0017] Compared with the prior art, the present invention has the following advantages: The pre-compressed fiber composite material cutting die provided by this invention utilizes a structural relationship where the buffer strip's longitudinal section comprises an upper and lower section; the upper section is fitted to the blade's sidewall; the lower section has an inclined structure with the distance between it and the blade's sidewall increasing away from the blade tip; and the top surface of the buffer strip has an initial height in its initial state, a compressed height in its compressed state, an initial height higher than the blade tip, and a compressed height lower than the blade tip, with the height difference between the two heights being greater than or equal to the thickness of the material to be cut. This allows the buffer strip to contact the material before the blade during cutting, achieving pre-compression. Furthermore, as the angle between the lower section and the blade holder surface decreases during blade entry, the vertical support force of the lower section on the upper section gradually decreases, causing the equivalent vertical stiffness of the buffer strip to decrease non-linearly with increasing compression. This maintains material compression while providing space for the blade. Consequently, material displacement during cutting is reduced, the resistance when the blade cuts through the material is lowered, and cutting defects are correspondingly reduced. Attached Figure Description

[0018] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the overall structure of the cutting die provided in the embodiment of this application.

[0020] Figure 2 This is a longitudinal sectional view of the cutting die provided in an embodiment of this application.

[0021] Figure 3 This is a schematic diagram showing the state of a cutting die cutting fiber composite material according to an embodiment of this application.

[0022] Figure 4 This is a partially enlarged structural diagram of the top protrusion of the buffer strip and the anti-stick coating provided in the embodiments of this application.

[0023] Figure 5 This is a schematic diagram of the blade cross-section structure provided in an embodiment of this application.

[0024] Figure 6 This is a partially enlarged structural diagram of the blade tip provided in an embodiment of this application.

[0025] The reference numerals in the figure are as follows: 10. Resin layer; 20. Fiber layer; 100. Blade holder; 200. Blade edge; 210. Edge tip arc; 220. Main cutting surface; 230. Stepped transition surface; 240. Secondary bevel; 300. Buffer strip; 310. Upper section; 320. Lower section; 330. Top surface; 340. Strip groove; 350. Protrusion; 360. Clearance gap; 370. Anti-stick coating; 380. Arc transition. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0027] The fiber composite material consists of a resin layer 10 and a fiber layer 20. During cutting, the material is prone to displacement and delamination. Existing compression methods struggle to balance compression and allow for spaced displacement. This embodiment utilizes the structural design of a buffer strip 300 to achieve compression before cutting, while also allowing for spaced displacement during cutting.

[0028] like Figures 1 to 3 As shown in the figure. This embodiment provides a pre-compressed fiber composite material cutting die, which mainly includes a blade holder 100, a blade 200, and a buffer strip 300.

[0029] Knife holder 100.

[0030] The blade 200 extends continuously along the product outline in a closed loop and is located on the top of the blade holder 100.

[0031] The buffer strip 300 extends continuously along the outline of the blade 200 in a closed loop shape and is located inside the blade 200. Its longitudinal section includes an upper section 310 and a lower section 320 that are distributed sequentially from the tip of the blade 200 toward the blade holder 100.

[0032] The upper section 310 fits against the side wall of the blade 200.

[0033] The lower section 320 is an inclined structure, and the distance between the inclined structure and the side wall of the blade 200 increases in the direction away from the tip of the blade 200.

[0034] The height of the top surface 330 of the buffer strip 300 in its initial state is called the initial height, and its height in the compressed state is called the compressed height. The initial height is higher than the tip of the blade 200. The compressed height is lower than the tip of the blade 200, and the height difference between the compressed height and the tip of the blade 200 is greater than or equal to the thickness of the material to be cut.

[0035] The closed-loop blade 200 corresponds to the product contour and determines the cutting shape. Optionally, the blade 200 is made of a high-hardness alloy.

[0036] The cushioning strip 300 is identical in shape to the blade 200 and accompanies it throughout the entire process, which helps to achieve compression and avoidance across the entire contour. Otherwise, the compression may be uneven, and local warping may occur. Optionally, the cushioning strip 300 is an elastomer.

[0037] The upper section 310 is responsible for fitting against the side wall of the blade 200, transmitting the clamping force and forming a seal; the lower section 320 is inclined to provide clearance space. This solves the problem that a single cross-section cannot simultaneously satisfy both clamping and clearance needs.

[0038] The 310mm surface of the upper section ensures more even pressure transmission and forms a sealed interface, reducing resin penetration. Point contact would lead to poor sealing and stress concentration. Optionally, the mating surfaces can be flat or curved.

[0039] The inclined structure of the lower section 320 provides lower vertical stiffness during compression, making the rubber strip easier to compress later and achieve clearance. Simultaneously, the inclined surface generates a component force pointing towards the blade 200, enhancing the seal. More importantly, as the lower section 320 changes angle due to rubber strip compression, the angle between the lower section 320 and the surface of the blade holder 100 gradually decreases. Therefore, the vertical support force provided to the upper section 310 decreases accordingly, dynamically adjusting the overall vertical stiffness of the rubber strip. Otherwise, the rubber strip would struggle to simultaneously satisfy both initial compression and later clearance requirements.

[0040] The initial height is higher than the tip of the blade 200, ensuring that the adhesive strip contacts the material before the blade 200, achieving pre-compression. Otherwise, if the blade 200 contacts first, the material may shift.

[0041] When the compression height is lower than the tip of the blade 200, and the height difference is greater than or equal to the thickness of the material to be cut, allowing the blade 200 to cut through the material, the rubber strip has been compressed below the tip of the blade 200 and does not hinder the cutting.

[0042] The closed-loop blade 200 and the buffer strip 300 provide a full-contour cutting and clamping base. Divided by longitudinal sections, the upper section 310 adheres to achieve high-rigidity clamping and sealing in the initial stage, while the lower section 320, tilted, utilizes geometric angle changes in the later stages of compression—that is, the angle between the lower section 320 and the blade holder 100 surface gradually decreases—to dynamically reduce the vertical support force and lower the equivalent stiffness of the rubber strip, automatically providing clearance space. The initial height being higher than the tip of the blade 200 allows for initial material clamping; the compression height being lower than the tip of the blade 200 with a height difference ≥ material thickness allows for cutting through the material. These features work together to achieve a physical mechanism of clamping first, then cutting, and clearance during the cut, thereby reducing material displacement and ensuring complete cutting. The absence of any feature breaks the mechanism. Therefore, this embodiment can achieve the cutting of fiber composite materials and reduce cutting defects.

[0043] Specifically, if the upper section 310 lacks contact with the side wall of the blade 200, the clamping force cannot be evenly transmitted to the material through the contact surface, and a sealed interface cannot be formed. Resin may seep in from the interface, and uneven transmission of clamping force will also lead to local stress concentration. If the inclined structure of the lower section 320 is lacking, the vertical stiffness of the buffer strip 300 increases approximately linearly with the amount of compression. In the later stage of the blade 200's cut, the buffer strip 300 still applies a large clamping force to the material, which cannot make way for the blade 200 to cut in. If the initial height is not higher than the tip of the blade 200, the blade 200 will contact the material before the buffer strip 300, and the material may be displaced in the early stage of cutting. If the compression height is not lower than the tip of the blade 200 and the height difference is greater than or equal to the thickness of the material to be cut, the buffer strip 300 may still be located below the tip of the blade 200 when the blade 200 cuts through the material, hindering the blade 200 from cutting through. The above features work together to achieve the process of "compressing first, then cutting, and making room for the cut". Without any one feature, the process cannot be fully realized.

[0044] It should be emphasized that the fit is for surface sealing and pressure transmission, and it forms a wedge-shaped clearance with the lower 320-degree tilt, generating dynamic support force changes during compression.

[0045] The angle change caused by the 320° tilt of the lower section during compression leads to a dynamic decrease in the vertical support force, achieving a geometric nonlinear stiffness of "hard first, soft later" rather than simply relying on material elasticity.

[0046] To improve the compression and clamping force of the buffer strip 300, in this embodiment, the height difference between the initial height and the tip of the blade 200 is 0.1-0.2 mm; the Shore hardness of the buffer strip 300 is 50-60 HA.

[0047] The height difference is just right; too small and the preload is insufficient, too large and it affects the blade's 200mm cutting depth. This hardness ensures the rubber strip is both soft enough to be compressed to the compression height and has enough elasticity to provide clamping force.

[0048] By varying the height and hardness ranges, the adhesive strip can undergo appropriate deformation during pre-compression and make room after compression, achieving a balance between compression and clearance. Therefore, by selecting the appropriate height and hardness within these ranges, this embodiment can be adapted to fiber composite materials of different thicknesses.

[0049] In this embodiment, the buffer strip 300 is a closed loop, with one side blocked by the blade 200. During compression, the lateral expansion mainly develops inward. At contour corners or turns, inward expansion may cause stress concentration, which in turn reacts on the blade 200, generating an outward lateral thrust. This thrust may affect the cutting perpendicularity, and under long-term action, may also cause the blade 200 material to break down.

[0050] To improve this problem, in this embodiment, the inner surface of the buffer strip 300 is provided with a plurality of strip-shaped grooves 340 extending in the vertical direction, and the strip-shaped grooves 340 are arranged at intervals along the circumference of the buffer strip 300.

[0051] The groove 340 extends vertically, providing deformation space for the inward expansion of the adhesive strip under pressure, thus releasing circumferential tensile stress. Without it, the inward expansion of the adhesive strip at corners is hindered, causing stress concentration and a reaction force on the blade 200, generating a lateral thrust on the blade 200. This could lead to deviations in cutting perpendicularity and increase the risk of blade 200 failure after long-term use. With the groove 340, the adhesive strip preferentially deforms inward when expanding, cutting off the lateral thrust transmitted towards the blade 200, while simultaneously releasing circumferential tensile stress.

[0052] The width, depth, and spacing of the grooves 340 can be set according to the cross-sectional dimensions, Shore hardness, and profile curvature of the buffer strip 300. Where the profile curvature radius is small, the inner expansion of the buffer strip 300 under pressure is greater; therefore, the spacing of the grooves 340 can be reduced accordingly, and the depth can be increased accordingly to provide greater deformation space. Where the curvature radius is large, the spacing of the grooves 340 can be increased accordingly, and the depth can be decreased accordingly. Optionally, the width of the grooves 340 is 5%-20% of the cross-sectional width of the buffer strip 300, the depth is 10%-40% of the cross-sectional height of the buffer strip 300, and the spacing between adjacent grooves 340 is 1-5 times the width of the grooves 340. These parameters, combined with a Shore hardness of 50-60 HA, ensure that the buffer strip 300 preferentially deforms into the grooves 340 during compression, reducing the lateral thrust transmitted towards the cutting edge 200.

[0053] The closed-loop structure of the buffer strip 300 expands inward upon compression; the strip groove 340 provides deformation space, releasing circumferential tensile stress and interrupting the lateral thrust transmitted towards the blade 200. The combination of these two elements reduces the lateral thrust of the strip on the blade 200, thereby helping to maintain cutting perpendicularity and reducing the risk of blade 200 breakage after long-term use. Therefore, this embodiment can improve the stress concentration problem that may occur at corners in this embodiment.

[0054] In this embodiment, the buffer strip 300 is in contact with the surface of the fiber composite material, and the resin in the prepreg has a certain degree of viscosity. During the cutting process, the resin may adhere to the surface of the buffer strip 300, affecting the elastic deformation of the strip and subsequent cleaning.

[0055] To reduce the adhesion between the cushioning strip 300 and the resin, in this embodiment, the cushioning strip 300 is made of silicone rubber, fluororubber, or fluorosilicone rubber.

[0056] Silicone rubber, fluororubber, or fluorosilicone rubber have low surface energy, making it difficult for resin to spread and adhere to their surfaces. Without them, resin adhesion to the surface of the cushioning strip 300 may reduce the effective elasticity of the strip, affecting the repeatability of the clamping and displacement actions, and increasing cleaning workload.

[0057] The buffer strip 300 is made of a low surface energy material, which directly reduces the adhesion between the resin and the surface of the strip. Therefore, this embodiment reduces resin adhesion to the strip surface, facilitating cleaning and helping to maintain the long-term stability of the strip's elastic deformation capacity.

[0058] like Figure 4As shown, as another embodiment to address the problem of adhesion between the buffer strip 300 and the fiber composite material, in this embodiment, the top surface 330 of the buffer strip 300 is provided with a protrusion 350 facing the cutting direction, and a clearance gap 360 is formed between the side of the protrusion 350 near the blade 200 and the side wall of the blade 200, and an anti-stick coating 370 is provided on the end face of the protrusion 350.

[0059] Setting an anti-stick coating 370 to reduce resin adhesion is a feasible anti-sticking method. However, the anti-stick coating 370 usually needs a certain hardness to achieve both wear resistance and anti-sticking. If the hard coating covers the edge of the rubber strip, the edge of the coating may scratch the material surface or the blade 200 when the rubber strip is repeatedly compressed and deformed. At the same time, the edge of the coating is also prone to cracking and peeling due to stress concentration.

[0060] The protrusion 350 concentrates the contact between the adhesive strip and the material on the end face of the protrusion 350, and the anti-stick coating 370 is only applied to the end face of the protrusion 350. The top surface 330 of the adhesive strip surrounding the protrusion 350 is an uncoated soft elastomer, and the edge of the coating is surrounded by the soft substrate and is not directly exposed to the contact area. A clearance gap 360 is formed between the side of the protrusion 350 near the blade 200 and the side wall of the blade 200. This gap provides space for the extruded resin and provides lateral clearance space for the protrusion 350 when the adhesive strip is deformed under pressure, so that the edge of the coating on the end face of the protrusion 350 does not touch the side wall of the blade 200, reducing the risk of the hard coating edge scratching the blade 200 or the material. The height and width of the protrusion 350 can be adjusted according to the material thickness and coating hardness.

[0061] It should be noted that after setting the protrusion 350, in the compressed state, the end face of the protrusion 350 constitutes the lowest compressed position of the buffer strip 300. That is, when judging whether the buffer strip 300 has made way for the cutting path of the blade 200, the height relationship between the end face of the protrusion 350 and the tip of the blade 200 should be used as the standard, rather than the top surface of the strip body around the protrusion 350. The top surface of the strip body around the protrusion 350 is lower than the end face of the protrusion 350 and does not constitute a pre-compression contact surface.

[0062] The coating further reduces the adhesion between the resin and the 350-degree end face, making the adhered resin easier to clean or remove with the material. The coating is applied only to the 350-degree end face, with the edges surrounded by a soft substrate, reducing the risk of scratching from hard edges.

[0063] The protrusion 350 concentrates contact on the end face, and the anti-stick coating 370 is only provided on the end face of the protrusion 350, so that the coating edge is surrounded by a soft elastomer around the protrusion 350, reducing the risk of the hard coating edge scratching the material or the blade 200. The clearance gap 360 provides lateral clearance space for the protrusion 350, so that the coating edge is away from the side wall of the blade 200 when the adhesive strip is compressed, while accommodating the squeezed resin. The anti-stick coating 370 reduces resin adhesion. These three factors work together to reduce resin accumulation and adhesion near the cutting edge and reduce the risk of coating edge scratching. Therefore, this embodiment can improve the resin accumulation problem during the cutting process and take into account both the wear resistance of the anti-stick coating 370 and edge safety.

[0064] It should be emphasized that the cooperation between the protrusion 350, the anti-stick coating 370, and the clearance 360, especially the fact that the coating edge is surrounded by the soft substrate and the clearance 360 ​​keeps the coating edge away from the cutting edge 200, solves the contradiction that "the coating needs to be hard but the hard edge is easy to scratch", rather than simply changing the shape.

[0065] In this embodiment, the edge of the top surface 330 of the buffer strip 300 facing the blade 200 is closest to the side wall of the blade 200 during the compression and rebound of the strip. If this edge is an acute angle, it may scrape the side wall of the blade 200 during compression, which may affect the surface quality of the blade 200 or even the integrity of the cutting edge after long-term use. If the top surface 330 is provided with an anti-stick coating 370, the coating edge is also prone to cracking and peeling due to stress concentration when it is an acute angle.

[0066] To improve this problem, in this embodiment, the edge of the top surface 330 of the buffer strip 300 facing the blade 200 is provided with an arc transition 380.

[0067] The 380° rounded transition transforms the edge from an acute angle into a smooth curved surface, reducing scratching against the sidewall of the blade 200 and dispersing stress at the coating edge, thus lowering the risk of coating cracking and peeling. Without it, the acute edge could scratch the blade 200, and the coating edge would be prone to failure. The radius of the rounded transition can be adjusted according to the compression of the adhesive strip and the coating thickness.

[0068] The rounded transition 380 at the edge of the top surface 330 makes the contact between this edge and the sidewall of the blade 200 smoother when the rubber strip is compressed, reducing scratching; at the same time, it disperses the stress at the edge of the coating, reducing the risk of coating cracking and peeling. Therefore, this embodiment can reduce the risk of scratching the blade 200 and extend the service life of the coating.

[0069] In this embodiment, the lower section 320 is an inclined structure, and the degree of inclination directly affects the clearance effect and the strength of the adhesive strip. If the included angle is too small, the lower section 320 will not provide enough clearance space in the vertical direction, and the adhesive strip may not be able to be compressed properly when the blade 200 cuts through; if the included angle is too large, the lower section 320 may deform excessively during compression, affecting the overall stability and rebound of the adhesive strip.

[0070] To improve this problem, in this embodiment, the angle between the outer surface of the lower section 320 and the side wall of the blade 200 is 10°-45°.

[0071] This range is beneficial for balancing the clearance effect and the strength of the rubber strip. If the included angle is too small, there will be insufficient clearance space; if the included angle is too large, the overall stiffness of the rubber strip will decrease too much, resulting in insufficient rebound.

[0072] By using a reasonable range of included angles, the lower 320° inclined surface can provide adequate clearance during compression, while maintaining sufficient strength and resilience of the rubber strip as a whole. Therefore, this embodiment improves the mechanical properties of the rubber strip.

[0073] In this embodiment, after the buffer strip 300 compresses the material, the blade 200 needs to cut into and sever the material under the compression condition. If the geometric design of the blade 200 is unreasonable, problems such as increased cutting resistance, fiber breakage, or splitting of the resin layer 10 may occur under the compression condition.

[0074] like Figure 5 As shown, to improve the cutting performance of the blade 200, in this embodiment, the cross-section of the blade 200 sequentially includes a tip arc 210, a main cutting surface 220, a stepped transition surface 230, and a secondary bevel 240; the radius of the tip arc 210 is 0.01-0.03 mm; the angle of the main cutting surface 220 is 30°-45° (see...). Figure 6 (Central angle a); the stepped transition surface 230 includes at least two steps, each step being 0.05mm wide, and the radius of the transition fillet between the steps being 0.015mm; the angle of the secondary slope 240 is 15°-20° (see...) Figure 6 (middle angle B).

[0075] The 210mm radius at the tip of the blade reduces the cutting of fiber bundles, and the radius range balances sharpness and strength.

[0076] The 220° angle range of the main cutting surface is beneficial for shearing fiber bundles without pulling them.

[0077] The stepped transition surface 230 has multiple steps that release shear stress step by step, reducing the splitting of the resin layer 10.

[0078] The secondary inclined plane at a 240-degree angle assists in guiding the uniform release of stress.

[0079] By utilizing the synergistic effects of various geometric features, the blade 200, while the material is pressed firmly by the buffer strip 300, can cleanly cut the fibers, reducing edge chipping and delamination. Therefore, this embodiment achieves a cut with improved quality.

[0080] In this embodiment, in order to improve the stress relief effect of the stepped transition surface 230, the stepped transition surface 230 includes 2-5 steps, and the height of each step gradually increases in the direction away from the tip of the cutting edge.

[0081] Multiple steps gradually reduce stress, and the increasing height further improves the stress gradient, allowing the shear stress to transition more smoothly to the secondary inclined plane 240.

[0082] By varying the number and height of the steps, stress is released gradually. Therefore, this embodiment can further suppress edge chipping.

[0083] In this embodiment, the blade 200 repeatedly cuts the fiber material under pressure, which makes the blade surface prone to wear, and the prepreg resin may adhere to the blade, affecting the cutting continuity and blade life.

[0084] To improve the wear resistance and non-stick properties of the blade 200, in this embodiment, the surface of the blade 200 is provided with a ceramic coating with a thickness of 5-10μm and a hardness ≥HV1200.

[0085] The ceramic coating increases surface hardness, reduces the coefficient of friction, and minimizes resin adhesion. Without it, the blade 200 is prone to wear and resin adhesion, affecting long-term cutting stability.

[0086] The ceramic coating provides wear resistance and non-stick protection, extending the blade life by 200%. Therefore, this embodiment maintains long-term cutting stability.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. All such modifications or substitutions should be covered within the protection scope of this application, and should not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application. Therefore, the protection scope of this application should be determined by the protection scope of the claims.

Claims

1. A pre-compressed fiber composite material cutting die, characterized in that, include: Knife Holder(100); The cutting edge (200) extends continuously along the product outline in a closed loop and is located on the top of the blade holder (100); A buffer strip (300) extends continuously along the outline of the blade (200) in a closed loop shape and is disposed on the inner side of the blade (200). Its longitudinal section includes an upper section (310) and a lower section (320) distributed sequentially from the tip of the blade (200) toward the blade holder (100). The upper section (310) is in contact with the side wall of the blade (200); The lower section (320) is an inclined structure, and the distance between the inclined structure and the side wall of the blade (200) increases in the direction away from the tip of the blade (200); The lower section (320) is configured such that, during the compression of the buffer strip (300), as the angle between the lower section (320) and the surface of the knife holder (100) decreases, the supporting force of the lower section (320) on the upper section (310) in the vertical direction gradually decreases, thereby causing the equivalent vertical stiffness of the buffer strip (300) to decrease nonlinearly with the increase of compression. The height of the top surface (330) of the buffer strip (300) in the initial state is the initial height, and the height in the compressed state is the compressed height; The initial height is higher than the tip of the blade (200) so that the buffer strip (300) contacts the material to be cut before the blade (200); The compression height is lower than the tip of the blade (200), and the height difference between the compression height and the tip of the blade (200) is greater than or equal to the thickness of the material to be cut, so that when the blade (200) cuts through the material to be cut, the buffer strip (300) has given way to the cutting path of the blade (200).

2. The pre-compressed fiber composite material cutting die according to claim 1, characterized in that, The height difference between the initial height and the tip of the blade (200) is 0.1-0.2 mm; the Shore hardness of the buffer strip (300) is 50-60 HA.

3. The pre-compressed fiber composite material cutting die according to claim 1, characterized in that, The inner surface of the buffer strip (300) is provided with a plurality of strip-shaped grooves (340) extending in the vertical direction, and the strip-shaped grooves (340) are arranged at intervals along the circumference of the buffer strip (300).

4. The pre-compressed fiber composite material cutting die according to claim 1, characterized in that, The buffer strip (300) is made of silicone rubber, fluororubber, or fluorosilicone rubber.

5. The pre-compressed fiber composite material cutting die according to claim 1, characterized in that, The top surface (330) of the buffer strip (300) has a protrusion (350) facing the cutting direction, and the end face of the protrusion (350) forms the contact surface between the buffer strip (300) and the material to be cut. In the compressed state, the end face of the protrusion (350) constitutes the lowest compressed position of the buffer strip (300), and the end face of the protrusion (350) is lower than the tip of the blade (200). The height difference between the end face of the protrusion (350) and the tip of the blade (200) is greater than or equal to the thickness of the material to be cut. The protrusion (350) forms a clearance gap (360) between the side of the blade (200) and the side wall of the blade (200), and the end face of the protrusion (350) is provided with an anti-stick coating (370).

6. The pre-compressed fiber composite material cutting die according to claim 1, characterized in that, The buffer strip (300) has a rounded transition (380) at the edge of its top surface (330) facing the blade (200).

7. The pre-compressed fiber composite material cutting die according to claim 1, characterized in that, The angle between the outer side of the lower section (320) and the side wall of the blade (200) is 10°-45°.

8. The pre-compressed fiber composite material cutting die according to claim 1, characterized in that, The cross section of the blade (200) includes, in sequence, the top arc of the blade tip (210), the main cutting surface (220), the stepped transition surface (230), and the secondary bevel surface (240). The radius of the arc (210) at the tip of the cutting edge is 0.01-0.03 mm; The angle of the main cutting plane (220) is 30°-45°; The stepped transition surface (230) includes at least two steps, each step having a width of 0.05 mm and a fillet radius of 0.015 mm between the steps; The angle of the secondary inclined plane (240) is 15°-20°.

9. A pre-compressed fiber composite material cutting die according to claim 8, characterized in that, The stepped transition surface (230) includes 2-5 steps, and the height of each step gradually increases in the direction away from the tip of the cutting edge.

10. A pre-compressed fiber composite material cutting die according to claim 1, characterized in that, The surface of the blade (200) is provided with a ceramic coating, the thickness of which is 5-10μm and the hardness is ≥HV1200.

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