Honeycomb core insert milling tool

Abstract

The utility model discloses a kind of honeycomb core material plunge milling cutters, including shank and tool bit, the tool bit is circular truncated cone, its side surface A is divided into two sections along length direction, transition section close to top surface and cutting edge section close to bottom surface, the included angle alpha of cutting edge section with the center line of tool bit is less than the included angle beta of transition section with the center line of tool bit, circular truncated cone's chip flute is opened from the bottom surface edge to the tool bit, the side surface B of chip flute and the cutting edge section form cutting edge, plunge milling cutter with the circumferential portion of cutting edge section is in vertical direction to honeycomb core side edge plunge milling processing.The utility model has the advantages that: plunge milling cutter is designed as circular truncated cone as a whole to tool bit, cutting edge is designed as relatively wide-mouthed structure, during plunge milling processing, the large diameter of conventional cylindrical plunge milling cutter can be effectively interfered with some structures on honeycomb core material part;Under the processing requirement of meeting honeycomb core side edge milling processing residual height, processing efficiency can be improved.

Description

Technical Field

[0001] This utility model relates to milling tools, and in particular to a milling cutter for aerospace composite honeycomb core materials. Background Technology

[0002] For aerospace composite honeycomb core materials, the CNC milling of the honeycomb core sides is generally carried out by milling or plunge milling.

[0003] Side milling with a cutting tool offers high processing efficiency, but results in poor precision and numerous fuzzy impurities on the machined side surface. Figure 1 The image shows plunge milling, also known as Z-axis milling. For machining difficult-to-machine materials, such as curved surfaces, grooving, and machining with large tool overhangs, plunge milling is far more efficient than conventional face milling, and produces a better side surface quality. However, for honeycomb core materials, the residual height of the side surface after machining is limited by the tool diameter and machining step distance. The average machining time for 1m of honeycomb core material is 1 to 1.5 hours, resulting in low machining efficiency. Utility Model Content

[0004] Purpose of this utility model: The purpose of this application is to provide a milling cutter for aerospace composite honeycomb core materials, which can improve processing efficiency as much as possible while meeting the processing requirements of residual height in the side milling of honeycomb core materials.

[0005] Technical solution: A milling cutter for honeycomb core material includes a shank and a cutter head. The cutter head is frustoconical, and its side surface A is divided into two sections along its length: a transition section near the top surface and a cutting edge section near the bottom surface. The angle α between the cutting edge section and the center line of the cutter head is smaller than the angle β between the transition section and the center line of the cutter head. A frustoconical chip removal groove is formed from the edge of the bottom surface towards the cutter head. The side surface B of the chip removal groove forms a cutting edge with the cutting edge section. The milling cutter performs milling on the side of the honeycomb core material with the circumferential portion of the cutting edge section in the vertical direction.

[0006] Furthermore, the included angle β is 3–8° larger than the included angle α, the included angle γ between the side surface B and the center line of the cutter head is 11–20° larger than the included angle α, and the length L of the cutting edge section along the center line of the cutter head is 3–8 mm. To ensure the cutter head, especially the cutting edge, meets certain structural strength requirements, the included angle γ, included angle α, and length L are designed. To ensure that when the cutting edge interacts with the side of the honeycomb core, the cutter head, except for the cutting edge, does not interfere with the side of the honeycomb core, the included angles β and α are designed to allow the transition section to avoid interference with the side of the honeycomb core.

[0007] The optimal configuration has an included angle α of 20°, an included angle β of 25°, an included angle γ of 35°, a length L of 5mm, good cutter head structure strength, and is suitable for plunge milling operations.

[0008] Furthermore, the relationship between the residual height H of the plunge milling, the radius R of the bottom surface, and the step distance S of the plunge milling is H = R - [R 2 -(S / 2) 2 ] 1 / 2 .

[0009] Ideally, the residual height H is 0.2 mm, and the radius R is 25 mm.

[0010] Furthermore, the centerline of the tool holder is aligned with the centerline of the tool head, and the tool as a whole has a centerline symmetrical structure, resulting in good overall structural strength and suitable operation for plunge milling.

[0011] Furthermore, the top surface transitions to the lower end of the tool holder with a rounded chamfer.

[0012] Beneficial effects: The advantages of this utility model are: the overall design of the milling cutter head is frustum-shaped, and the cutting edge is designed with a relatively wide opening structure. During milling, it can effectively prevent interference between the large diameter of conventional cylindrical milling cutters and some structures on the honeycomb core material parts; while meeting the processing requirements of the residual height of the side milling of the honeycomb core, it can improve the processing efficiency. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of a plunge milling process;

[0014] Figure 2 This is a schematic diagram of the milling cutter structure of this utility model;

[0015] Figure 3 This is a schematic diagram of the cutter head structure;

[0016] Figure 4 This is a schematic diagram illustrating the use of the milling cutter of this utility model;

[0017] Figure 5 This is a schematic diagram illustrating the use of a conventional cylindrical plunge milling cutter.

[0018] Figure 6 This chart compares the machining efficiency of conventional cylindrical plunge milling cutters and the plunge milling cutter of this invention to achieve the same machining residual height. Detailed Implementation

[0019] The present application will be further explained below with reference to the accompanying drawings and specific embodiments.

[0020] A type of milling cutter for honeycomb core material, as shown in the attached figure. Figure 2 As shown, the tool includes a tool holder 1 and a tool head 2. These can be a single, integral piece or a single piece formed by connecting the lower end of the tool holder to the upper end of the tool head. The material is high-speed steel or cemented carbide. The upper end of the tool holder 1 is the clamping area for the tool during plunge milling.

[0021] Cutter head 2 is used to directly engage with the side of the honeycomb core to complete the plunge milling process, combined with the attached... Figure 3 As shown, its shape is a frustum, with a top surface 22, a bottom surface 23, and a circumferential side surface A21 between the two. The side surface A21 is divided into two segments along the length of the tool: a transition segment 211 near the top surface 22 and a cutting edge segment 212 near the bottom surface 23. The transition segment 211 and the cutting edge segment 212 have different inclination angles with the center line of the tool head 2. The cutting edge segment 212 forms an angle α with the center line of the tool head 2, and the transition segment 211 forms an angle β with the center line of the tool head 2. The angle α is smaller than the angle β, that is, the angle α is steeper than the angle β. The chip removal groove 24 is formed from the circumferential edge of the bottom surface 23 into the inside of the cutter head 2. Its shape is also a frustum. The circumferential side surface B241 of the chip removal groove 24 forms an angle γ with the center line of the cutter head 2. The side surface B241 and the cutting edge section 212 form the cutting edge 25. The length of the cutting edge section 212 on the side surface A21 is the length E of the cutting edge 25. The length of the cutting edge section 212 along the center line of the cutter head 2 is denoted as L. Obviously, the height of the frustum of the chip removal groove 24 must be less than the height of the frustum of the cutter head 2.

[0022] Combined with appendix Figure 4 As shown, when the plunge milling cutter is used, the cutter rotates at a low speed and the cutting edge 25 acts circumferentially on the side of the honeycomb core for plunge milling. The cutting edge 212 of the cutting edge must be in the vertical direction and parallel to the side of the honeycomb core. The cutter plunges vertically downward to perform plunge milling on the side of the honeycomb core. The chip removal groove 24 provides space for the discharge of waste generated by milling.

[0023] To ensure the cutting head, especially the cutting edge, meets certain structural strength requirements, the included angle γ is designed to be 11–20° larger than the included angle α, and the length L is 3–8 mm. To prevent interference between the cutting edge and the honeycomb core side when the cutting edge interacts with it, the included angle β is designed to be 3–8° larger than the included angle α, thus separating the transition section 211 from the honeycomb core side. For example, with included angle α of 20°, included angle β of 25°, included angle γ of 35°, and length L of 5 mm, the cutting head has good structural strength and is suitable for plunge milling operations. The surface roughness of the cutting edge section 212 reaches 0.4 μm, resulting in good surface quality of the machined honeycomb core side.

[0024] Generally, the centerline of the tool holder 1 is aligned with the centerline of the tool head 2, and the tool as a whole has a symmetrical structure along the centerline. The overall structure of the tool has good strength and is suitable for plunge milling operations. The top surface 22 of the tool head 2 transitions to the lower end of the tool holder 1 with a rounded chamfer 26.

[0025] The following is an example of conventional cylindrical plunge milling machining. Figure 5 As shown, the tool is vertically downward and parallel to the side of the honeycomb core. It is evident that during plunge milling, the non-plunge area of ​​the tool interferes with some structures on the honeycomb core part. (See attached image) Figure 4As shown, the plunge milling cutter of this application has an overall frustum-shaped cutter head and a relatively wide-mouthed cutting edge. During plunge milling, it can effectively prevent interference between the large diameter of conventional cylindrical plunge milling cutters and some structures on honeycomb core material parts.

[0026] The milling cutter described in this application can improve machining efficiency while meeting the machining requirements for the residual height in the side milling of honeycomb cores. (See attached...) Figure 6 As shown, the left side uses a conventional cylindrical plunge milling cutter with a diameter of 20mm, i.e., a radius R of 10mm; the right side uses the plunge milling cutter of this application, with a circumferential radius R of the bottom surface 23 of the cutter head 2 of 25mm. Both cutters perform plunge milling on the same honeycomb core. To achieve the same machining residual height H of 0.2mm, the step distance S of the conventional cylindrical plunge milling cutter is approximately 3.98mm, requiring plunge milling to be controlled at approximately 3.8mm. The step distance S of the plunge milling cutter of this application is approximately 6.31mm, allowing the plunge milling to increase the step distance to 6.5mm, thus nearly doubling the machining efficiency. The relationship between the residual height H, radius R, and step distance S of the plunge milling is H = R - [R...]. 2 -(S / 2) 2 ] 1 / 2 .

[0027] As can be seen, the plunge milling cutter of this application has a larger radius R than conventional cylindrical plunge milling cutters. This not only prevents interference with some structures on the honeycomb core material parts and preserves the high quality of the product's machined surface, but also significantly improves the plunge milling efficiency.

Claims

1. A honeycomb core material plunge milling tool comprising a shank (1) and a head (2), characterized in that: The cutter head (2) is frustum-shaped, and its side surface A (21) is divided into two sections along the length direction: a transition section (211) near the top surface (22) and a cutting edge section (212) near the bottom surface (23). The angle α between the cutting edge section (212) and the center line of the cutter head (2) is smaller than the angle β between the transition section (211) and the center line of the cutter head (2). A frustum-shaped chip removal groove (24) is opened from the edge of the bottom surface (23) into the cutter head (2). The side surface B (241) of the chip removal groove (24) and the cutting edge section (212) form a cutting edge (25). The milling cutter mills the side of the honeycomb core with the circumferential part of the cutting edge section (212) in the vertical direction.

2. The honeycomb core slotting tool of claim 1, wherein: The included angle β is 3 to 8° larger than the included angle α, the included angle γ between the side surface B (241) and the center line of the cutter head (2) is 11 to 20° larger than the included angle α, and the length L of the cutting edge section (212) along the center line of the cutter head (2) is 3 to 8 mm.

3. The honeycomb core slot milling tool of claim 2, wherein: The included angle α is 20°, the included angle β is 25°, the included angle γ is 35°, and the length L is 5mm.

4. The honeycomb core slotting tool of claim 1, wherein: The relationship between the residual height H of the plunge milling, the radius R of the bottom surface (23), the step S of the plunge milling is H = R - [R 2 -(S / 2) 2 ] 1 / 2 .

5. The honeycomb core slot milling tool of claim 4, wherein: If the remaining height H is 0.2 mm, then the radius R is 25 mm.

6. The honeycomb core slotting tool of claim 1, wherein: The center line of the handle (1) is consistent with the center line of the blade (2).

7. The honeycomb core slotting tool of claim 1, wherein: The top surface (22) transitions to the lower end of the handle (1) with a rounded chamfer (26).

Images