A drilling and milling integrated composite tool

Abstract

This utility model discloses a drilling and milling integrated composite tool, comprising: a shank and a cutting edge coated with a diamond coating; the front end of the cutting edge consists of a drill tip assembly composed of two cutting edges; the cutting edge is circumferentially provided with cutting edges A, B, C, and D; cutting edge A has a right-handed tooth-breaking groove, cutting edge C has a left-handed tooth-breaking groove, and chip removal grooves are provided axially between cutting edges A, B, C, and D; the first tooth of cutting edges A, B, C, and D near the drill tip assembly is 0.1 mm smaller in diameter than the tooth at the rear end. By designing a drill tip assembly with two cutting edges at the front end of the tool, and a composite tool with four circumferential cutting edges, the four adjacent cutting edges are designed with different rotation directions, each cutting edge has its own specific function at the cutting point, and chip removal is easy. During cutting, there is no chip accumulation at the cutting edge, resulting in an extremely smooth and high-gloss surface of the machined product, while reducing delamination and burr occurrence by 100%; the diamond coating on the surface has a lifespan five times that of traditional tools.

Description

Technical Field

[0001] This utility model relates to the field of machining tool technology, specifically to a high-efficiency composite machining tool that integrates drilling and milling for carbon fiber, glass fiber and carbon-based composite materials. Background Technology

[0002] Fiber composite materials are widely used in high-precision fields such as aerospace and new energy due to their excellent properties such as high specific strength and high specific modulus. However, their anisotropy, low interlaminar strength, and high hardness (e.g., carbon fiber typically has a hardness of HRC50-60) make them typical difficult-to-machine materials in hole machining. Existing technologies mainly use conventional cutting tools such as twist drills and milling cutters, which have the following inherent defects that urgently need to be addressed:

[0003] 1. Cumbersome processes and low efficiency: To ensure hole quality (such as dimensional accuracy and inlet / outlet morphology), current processes generally adopt a multi-step separation scheme of "drilling before milling" or "drilling before reaming." That is, a pre-hole is first machined with a drill bit, and then a milling cutter or reamer is used for finishing. Multiple clamping and tool changing operations severely restrict the level of production automation and processing efficiency.

[0004] 2. Severe tool wear and short tool life: Carbon fiber has high hardness and strong abrasive properties. The cutting edges of traditional high-speed steel or cemented carbide tools wear rapidly during high-speed cutting, resulting in extremely short tool life. Frequent tool changes not only increase tool costs but also reduce equipment utilization due to downtime, leading to high overall production costs.

[0005] 3. Poor processing quality and high defect rate: The drilling force and tearing effect of traditional drill bits can easily lead to the separation of material layers (delamination defects), especially on the exit side of the hole; at the same time, burrs and tears that are difficult to remove are easily generated at the entrance and exit edges of the hole. Utility Model Content

[0006] The purpose of this utility model is to solve the problems in the existing technology and propose a drilling and milling composite tool. It is a composite tool with a drill tip combination with two cutting edges and four peripheral cutting edges. The four peripheral cutting edges are designed with different rotation directions. Each cutting edge has its own division of labor in the cutting point. Moreover, chip removal is easy. There is no chip accumulation at the cutting edge during cutting, which makes the edge surface of the machined product extremely smooth and has a high degree of finish. At the same time, the delamination and burr occurrence rate is reduced by 100%. The surface is coated with a diamond coating, which has a lifespan 5 times that of traditional tools.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a drilling and milling integrated composite tool, comprising: a shank and a cutting edge coated with a diamond coating, the front end of the cutting edge being a drill tip assembly composed of two cutting edges, and the circumference of the cutting edge being provided with A-edge, B-edge, C-edge and D-edge with different rotation directions of adjacent cutting edges, and multiple A-edge, B-edge, C-edge and D-edge being arranged along the axial direction of the cutting edge; the cutting edge of A-edge is provided with a right-handed tooth breaking groove, the cutting edge of C-edge is provided with a left-handed tooth breaking groove, and chip removal grooves are provided axially between A-edge, B-edge, C-edge and D-edge; the first tooth of A-edge, B-edge, C-edge and D-edge near the drill tip assembly is 0.1mm smaller in diameter than the tooth diameter of the rear tooth, so as to achieve integrated roughing and finishing.

[0008] This integrated drilling and milling tool achieves high-efficiency, high-quality machining through its unique cutting edge design. Specifically, the drill tip assembly, composed of two cutting edges, rapidly penetrates the material, while four peripheral cutting edges (A, B, C, and D edges) handle subsequent reaming and milling operations. Because adjacent cutting edges rotate in different directions, each edge undertakes a specific task during cutting, and this division of labor significantly improves machining efficiency. Simultaneously, the chip evacuation design allows for rapid chip removal, preventing chip accumulation at the cutting edges and ensuring a smooth and even machined surface. Furthermore, the first tooth near the drill tip assembly has a diameter 0.1mm smaller than the teeth at the rear; this detailed design enables the tool to perform both roughing and finishing operations simultaneously, further improving machining quality and efficiency. The diamond coating significantly extends the tool's lifespan by five times compared to traditional tools.

[0009] Preferably, the drill tip angle of the drill tip assembly is 90°-100°, and the eccentricity of the drill tip angle is 0.06±0.01mm.

[0010] Preferably, the spacing between each set of cutting edges (A, B, C, and D) is 1.25 ± 0.02 mm.

[0011] As a preferred embodiment, the main cutting edge of the B-edge has a back angle width of 0.05–0.08 mm and a back angle of 14°, a main cutting groove bottom diameter of 3.21 ± 0.01 mm and a front angle of 12°, and the main cutting edge of the C-edge near the drill tip assembly has a main cutting edge width of 0.15–0.20 mm and a tip angle of 10° ± 1°.

[0012] Preferably, the bottom diameter of the left-handed break-tooth cutting groove is 3.96±0.01mm, its rake angle is 12°, and the distance between the two left-handed break-tooth cutting grooves on the same cutting edge is 1.6±0.02mm.

[0013] Preferably, the bottom diameter of the right-handed break tooth cutting groove is 3.96±0.01mm, its rake angle is 12°, and the distance between the two right-handed break tooth cutting grooves on the same cutting edge is 1.6±0.02mm.

[0014] Preferably, the main cutting edge width of the D-edge near the drill tip assembly is 0.15–0.20 mm, and its tip width is 0.11 ± 0.02 mm.

[0015] Preferably, the width of blades A, B, C, and D is 1.8 ± 0.03 mm.

[0016] The drilling and milling composite tool provided by this utility model, through its innovative structural design, comprehensively solves the above-mentioned technical problems and achieves the following significant beneficial effects:

[0017] 1. It achieves process integration and greatly improves production efficiency: It integrates drilling and milling functions into one tool, realizing "one-cut forming", eliminating the time for changing tools and secondary clamping, which is particularly suitable for automated continuous production of CNC machine tools, and can increase production efficiency by more than 50%.

[0018] 2. Significantly improves tool life and reduces production costs: The diamond coating on the cutting edge has extremely high hardness and wear resistance, which can effectively resist the abrasion of carbon fiber, increasing tool life several times compared to traditional tools, reducing the number of tool changes and tool procurement costs.

[0019] 3. Improved machining quality and significantly reduced defect rate: The drill tip assembly at the front end is responsible for centering and drilling; the A, B, C, and D cutting edges, rotating in different directions (left-hand and right-hand), cancel each other out during milling, effectively suppressing vibration and ensuring smooth machining, thereby reducing burr formation. The broken tooth groove design: The right-hand broken tooth groove on the A edge and the left-hand broken tooth groove on the C edge can sharply cut the carbon fiber bundle, rather than tearing or pulling it out, resulting in a smoother hole wall. The design of the first tooth being 0.1mm smaller in diameter than the rear teeth creates a tiny step. After the first tooth completes the initial cutting, subsequent teeth perform finishing, distributing the cutting force and providing more space for chip removal. This effectively prevents delamination defects and significantly reduces the occurrence of delamination and burrs.

[0020] 4. Ensure machining accuracy and stability: By precisely controlling parameters such as the back angle, front angle, groove bottom diameter, and cutting width of each cutting edge, the cutting process is ensured to be smooth and stable, reducing vibration and thus obtaining high-quality holes with high dimensional accuracy, high roundness, and good surface roughness. Attached Figure Description

[0021] Figure 1 This is the front view of the present invention;

[0022] Figure 2 This is the left view of the present invention;

[0023] Figure 3 This is a schematic diagram of the structure of blade A in this utility model;

[0024] Figure 4 This is a schematic diagram of the structure of blade B in this utility model;

[0025] Figure 5 This is a schematic diagram of the C-blade in this utility model;

[0026] Figure 6 This is a schematic diagram of the structure of the D-blade in this utility model.

[0027] Figure 7 for Figure 4 A magnified structural diagram of point A in the middle. Detailed Implementation

[0028] To make the above-mentioned objects, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0029] Please see Figures 1 to 7 The present invention provides a drilling and milling integrated composite tool, which is mainly composed of a shank 1 and a cutting edge 2. A diamond coating is applied to its surface by chemical vapor deposition process to provide extremely high surface hardness and wear resistance.

[0030] The front end of the cutting edge 2 is designed with a drill tip assembly 20 for centering and preliminary drilling, which consists of two intersecting main cutting edges. Preferably, the drill tip angle of the drill tip assembly 20 is set to 98° and its eccentricity is set to 0.06 mm. This design helps to reduce axial cutting force and suppress exit delamination.

[0031] The cutting edge 2 has four sets of cutting edges along its circumference, namely A-edge 21, B-edge 22, C-edge 23, and D-edge 24. Multiple A-edges, B-edges, C-edges, and D-edges are arranged along the axial direction of the cutting edge 2. The rotation directions of the four sets of cutting edges are different, and adjacent cutting edges rotate in opposite directions. This design can cancel out radial cutting forces during milling, effectively suppressing machining vibration and thus improving the surface quality of the hole wall. Chip removal grooves 25 are formed between each set of cutting edges along the axial direction of the cutting edge 2 to smoothly remove chips generated during cutting, preventing chip blockage that could cause tool overheating or damage.

[0032] To further optimize cutting performance and suppress machining defects, the following key design features are adopted in this utility model:

[0033] A right-handed breaking tooth groove 210 is machined on the cutting edge of blade A 21, and a left-handed breaking tooth groove 230 is machined on the cutting edge of blade C 23. These breaking tooth grooves can cut the carbon fiber filaments instead of pulling them out, thereby effectively reducing the generation of burrs. In this embodiment, the bottom diameter of the breaking tooth groove is 3.96 mm, its rake angle is 12°, and the distance between two adjacent breaking tooth grooves on the same cutting edge is 1.6 mm.

[0034] The diameter of the first tooth (i.e., the first tooth) of the A-flute 21, B-flute 22, C-flute 23, and D-flute 24 near the drill tip assembly 20 is 0.1 mm smaller than the diameter of its subsequent teeth. For example, the diameter of the first tooth is 5.90 mm, and the diameter of the subsequent teeth is 6.00 mm. This design creates a tiny step, allowing the first tooth to pre-cut, removing most of the material and forming a pre-hole, before the subsequent teeth perform finishing and reaming. This structure significantly reduces the cutting force and heat during the final cut, and is a key technology for solving the exit delamination problem.

[0035] Among them, the main cutting edge width of the B-blade 22 can be 0.06mm, its back angle is 14°, its main cutting groove bottom diameter is 3.21mm, and its front angle is 12°.

[0036] The main cutting edge width of the C-blade 23 near the drill tip assembly 20 can be 0.18mm, and its tip angle is 10°.

[0037] The main cutting edge width of the D-blade 24 near the drill tip assembly 20 can be 0.18mm, and its tip width is 0.11mm.

[0038] The width of all four cutting edges is uniformly 1.8mm, and the distance between the cutting edges of each group is 1.25mm.

[0039] These precisely calculated and optimized parameters work together to ensure a smooth, stable, and low-vibration cutting process, ultimately achieving high-precision and low-defect machining results.

[0040] The working process is as follows: The cutting tool rotates at high speed and feeds under the drive of the machine tool spindle. First, the drill tip assembly 20 at the front end cuts into the workpiece, completing centering and drilling. Subsequently, the circumferentially distributed cutting edges A, B, C, and D sequentially cut the hole wall. Among them, the left and right helical cutting grooves on cutting edges A 21 and C 23 efficiently shear fibers like scissors, while cutting edges B 22 and D 24 are mainly responsible for finishing the hole wall. The chips are smoothly discharged through the chip removal groove 25. The entire process is completed in one feed, realizing the composite machining of drilling and milling.

[0041] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A drilling and milling integrated composite tool, characterized in that, include: The shank and cutting edge are coated with a diamond coating. The front end of the cutting edge consists of a drill tip assembly composed of two cutting edges. The circumference of the cutting edge has A, B, C, and D cutting edges with different rotation directions for adjacent cutting edges. There are multiple A, B, C, and D cutting edges arranged along the axial direction of the cutting edge. The cutting edge A has a right-handed tooth breaking groove, and the cutting edge C has a left-handed tooth breaking groove. Chip removal grooves are provided axially between the A, B, C, and D cutting edges. The first tooth of the A, B, C, and D cutting edges near the drill tip assembly is 0.1 mm smaller in diameter than the tooth at the rear end to achieve integrated roughing and finishing.

2. The drilling and milling integrated composite tool according to claim 1, characterized in that, The drill tip angle of the drill tip assembly is 90°-100°, and the eccentricity of the drill tip angle is 0.06±0.01mm.

3. The drilling and milling integrated composite tool according to claim 1, characterized in that, The spacing between each set of cutting edges (A, B, C, and D) is 1.25 ± 0.02 mm.

4. The drilling and milling integrated composite tool according to claim 1, characterized in that, The main cutting edge width of the B-edge is 0.05–0.08 mm, its back angle is 14°, the diameter of the main cutting groove bottom is 3.21 ± 0.01 mm, and its rake angle is 12°. The main cutting edge width of the C-edge, which is close to the drill tip assembly, is 0.15–0.20 mm, and its tip angle is 10° ± 1°.

5. The drilling and milling integrated composite tool according to claim 1, characterized in that, The bottom diameter of the left-handed break tooth cutting groove is 3.96±0.01mm, its rake angle is 12°, and the distance between the two left-handed break tooth cutting grooves on the same cutting edge is 1.6±0.02mm.

6. The drilling and milling integrated composite tool according to claim 1, characterized in that, The bottom diameter of the right-handed break tooth cutting groove is 3.96±0.01mm, its rake angle is 12°, and the distance between the two right-handed break tooth cutting grooves on the same cutting edge is 1.6±0.02mm.

7. The drilling and milling integrated composite tool according to claim 1, characterized in that, The main cutting edge width of the D-edge near the drill tip assembly is 0.15–0.20 mm, and its tip width is 0.11 ± 0.02 mm.

8. The drilling and milling integrated composite tool according to claim 1, characterized in that, The width of blades A, B, C, and D is 1.8 ± 0.03 mm.

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