High-hardness die fillet milling cutter

Abstract

The invention relates to a high-hardness die fillet milling cutter, which is applied to the technical field of milling cutters, and comprises a cutter handle and a cutting part arranged at one end of the cutter handle, and the cutting part comprises a plurality of cutting edges and a spiral chip groove. The tool nose fillet blade is of the arc structure and adopts the variable rake angle structure, the design can reduce cutting resistance, improve the strength and durability of the tool nose arc and reduce vibration and noise in the cutting process, and the arc-shaped structure ensures the stability of end blade cutting and circumferential blade cutting, avoids tipping of the tool nose and improves the cutting efficiency. The end edge, the circumferential edge and the tool nose fillet edge are all subjected to blunt rounding treatment, microdefects of the cutting edge are reduced, and the cutting stability is improved. The cutting edge in the obtuse round shape can reduce the interaction force in the cutting process and reduce the cutting heat and abrasion in the machining process, so that the strength of the cutting edge is higher, and the service life of the cutter is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of milling cutters, in particular to a high-hardness mold rounded corner milling cutter. Background Art

[0002] High-hardness die steel, with a hardness range usually above HRC50, is used in the automotive, electronics, aerospace, medical equipment and other fields. It is an indispensable and important material in industrial production, but it also faces many processing difficulties.

[0003] Mold steel usually has high hardness and high strength, which makes the tool susceptible to wear during the cutting process. Mold steel with high hardness needs to withstand greater cutting force and friction during cutting, resulting in a shortened tool life. Mold steel has good thermal conductivity, which means that the heat generated during the cutting process is easily transferred to the tool, further exacerbating the wear of the tool. Some mold steels have larger specifications, such as mold steels that can reach several meters in height, which makes it difficult to transfer the cutting force to the material, increasing the difficulty of cutting. As the application field of mold steel continues to expand, the requirements for its processing technology and process are also getting higher and higher. For example, the processing of automotive molds and mobile phone molds requires high precision and high efficiency, and also needs to meet complex surface processing and structural size requirements.

[0004] At present, high precision and high efficiency are generally achieved by increasing the cutting speed or increasing the number of tool teeth. However, increasing the cutting speed will easily increase the cutting resistance and cause tool vibration, resulting in increased tool wear. Increasing the number of tool teeth will easily lead to poor chip removal and scratches on the workpiece surface.

[0005] In view of this, there is an urgent need for a high-hardness mold radius milling cutter to solve the above problems. Summary of the invention

[0006] In order to help solve the problems existing in the prior art, the present invention provides a high-hardness mold milling cutter, which adopts the following technical solution: comprising: a milling cutter body, the milling cutter body comprising a tool handle and a cutting portion arranged at one end of the tool handle, the cutting portion comprising a plurality of cutting edges and a spiral chip groove, the cutting edge comprising an end edge arranged at the bottom of the cutting portion, a peripheral edge arranged around the cutting portion, and a tool tip rounded edge connecting the end edge and the corresponding peripheral edge;

[0007] The end blade comprises a plurality of long teeth and a plurality of short teeth, the blade tip rounded corner blade is in an arc shape, and the blade tip rounded corner blade is a variable rake angle structure;

[0008] The end edge has an end edge rake face, an end edge flank face, and an end edge blunt circle for connecting the end edge rake face and the end edge flank face;

[0009] The circumferential blade has a circumferential blade rake surface, a circumferential blade flank surface, and a circumferential blade blunt circle for connecting the circumferential blade rake surface and the circumferential blade flank surface;

[0010] The rounded blade tip has a rounded blade rake face, a rounded blade flank face, and a rounded blade blunt circle for connecting the rounded blade rake face and the rounded blade flank face;

[0011] The end edge rake face, the peripheral edge rake face and the tip rounded edge rake face form a spiral chip removal groove.

[0012] It is further characterized in that

[0013] The end blade includes a long tooth and a short tooth, and the long teeth and the short teeth are arranged at intervals.

[0014] The outer diameter of the cutting portion is D, and the radius of the blade tip rounded edge is R, satisfying 0.03D≤R≤0.2D.

[0015] The core thickness diameter of the milling cutter body is d, which satisfies d=70%D.

[0016] The variable rake angle structure includes three rake angles, namely α, β and γ, and the degrees of the three rake angles are respectively -3°, -2° and -3°.

[0017] The front angle θ1 of the front cutting edge of the end edge is a negative value, satisfying -3°≤θ≤-5°, and the back angle θ2 of the end edge is a positive value, satisfying 8°≤θ2≤12°.

[0018] The front angle ε1 of the front cutting edge of the peripheral blade is a negative value, satisfying -2°≤ε1≤-8°, and the back angle ε2 of the peripheral blade is a positive value, satisfying 10°≤ε2≤15°.

[0019] The radius of the end edge blunt circle, the radius of the peripheral edge blunt circle 403 and the radius of the rounded edge blunt circle are all r, satisfying 6μm≤r≤12μm.

[0020] The cutting part is provided with a coating, and the coating material is a multilayer structure composed of titanium nitride, chromium nitride or nitride aluminum titanium.

[0021] The tool handle and the cutting part are made of nanocrystalline material.

[0022] The above structure of the present invention can achieve the following beneficial effects:

[0023] The high-hardness mold radius milling cutter of the present invention has a radiused blade tip with an arc structure. This design can reduce cutting resistance, increase the strength and durability of the arc tip, and reduce vibration and noise during the cutting process. The arc-shaped structure can also make the cutting edge smoother and improve cutting efficiency.

[0024] The high-hardness mold rounded corner milling cutter of the present invention has a variable rake angle of the rounded corner edge of the tool tip, which can change the distribution of the cutting force. When the rake angle of the rounded corner edge of the tool tip changes, the contact area and contact angle of the cutting edge and the material will also change accordingly, which will cause the distribution of the cutting force on the cutting edge to change, making the cutting smoother. The curvature radius R of the rounded corner edge of the tool tip is 0.03D-0.2D, so the contact length between the rounded corner edge and the cut material is short, the cutting resistance is reduced, and thus the chipping of the rounded corner edge can be prevented.

[0025] The high-hardness mold radius milling cutter of the present invention has end edges, peripheral edges and tip radius edges configured as blunt-round cutting edges, which can reduce interaction forces, reduce cutting heat and wear during machining, make the cutting edges stronger, and thus extend the service life of the tool.

[0026] The high-hardness mold rounded corner milling cutter of the present invention has a negative rake angle θ1 of the end edge rake face and a negative rake angle ε1 of the peripheral edge rake face, which can make the cutting edge have higher strength and a longer service life when cutting high-hardness materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application;

[0028] Figure 2 It is a schematic diagram of the structure of the end blade of the embodiment of the present application;

[0029] Figure 3 Schematic diagram of the structure of the rounded edge of the blade tip in the embodiment of the present application;

[0030] Figure 4 It is a structural schematic diagram used to reflect the front and rear angles of the end blade in an embodiment of the present application.

[0031] Figure 5 It is a structural schematic diagram used to reflect the front and rear angles of the peripheral blade in an embodiment of the present application.

[0032] Figure 6 It is a schematic structural diagram of an embodiment of the present application for reflecting the bluntness of the cutting edge.

[0033] Figure numerals: 1. shank; 2. cutting part; 3. end edge; 301. end edge rake face; 302. end edge flank face; 303. end edge blunt rounded; 4. peripheral edge; 401. peripheral edge rake face; 402. peripheral edge flank face; 403 peripheral edge blunt rounded; 5. rounded tip edge; 501. rounded tip edge rake face; 502. rounded tip edge flank face; 503. rounded tip edge blunt rounded; 6. long teeth; 7. short teeth; 8. chip groove. DETAILED DESCRIPTION

[0034] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0035] It should be noted that the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, apparatus, product or equipment comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0036] The following is combined with Figure 1-6 The present invention is described in further detail.

[0037] Reference Figure 1-6 A high-hardness mold milling cutter comprises: a milling cutter body, the milling cutter body comprises a tool handle 1 and a cutting part 2 arranged at one end of the tool handle 1, the cutting part 2 comprises a plurality of cutting edges and a spiral chip groove 8 (a spiral chip groove 8 is arranged between adjacent cutting edges), the cutting edge comprises an end edge 3 arranged at the bottom of the cutting part 2, a peripheral edge 4 arranged around the cutting part, and a tip rounded edge 5 connecting the end edge 3 and the corresponding peripheral edge 4; the end edge 3 comprises a plurality of long teeth 6 and a plurality of short teeth 7, the tip rounded edge 5 is in an arc shape, and the tip rounded edge 5 is a variable front angle structure; the end edge 3 has an end edge front cutting face 301, an end edge rear cutting face 302, and an end edge rear cutting face 303. The blade surface 302 and the end blade blunt circle 303 for connecting the end blade front blade surface 301 and the end blade back blade surface 302; the peripheral blade 4 has a peripheral blade front blade surface 401, a peripheral blade back blade surface 402 and a peripheral blade blunt circle 403 for connecting the peripheral blade front blade surface 401 and the peripheral blade back blade surface 402; the tip rounded blade 5 has a rounded blade front blade surface 501, a rounded blade back blade surface 502 and a rounded blade blunt circle 503 for connecting the rounded blade front blade surface 501 and the rounded blade back blade surface 502; the end blade front blade surface 301, the peripheral blade front blade surface 401 and the blade tip rounded blade front blade surface 501 constitute a spiral chip groove 8.

[0038] Since the blade tip radius edge 5 is an arc structure, this design can reduce cutting resistance, increase the strength and durability of the blade tip arc, and reduce vibration and noise during the cutting process. The arc structure can also make the cutting edge smoother and improve cutting efficiency.

[0039] like Figure 2As shown, several end cutting edges 3 are divided into long teeth 6 and short teeth 7, and the long teeth 6 and the short teeth 7 are arranged at intervals, and the tooth expansion angle is 90 degrees to 110 degrees (for example, 90 degrees, 100 degrees, 110 degrees, etc.), and the upper and lower and left and right deviations of the tooth expansion angle are 0.2mm-0.3mm. The alternating arrangement of long teeth 6 and short teeth 7 can optimize the geometry of the cutting edge and increase the chip space of the end teeth.

[0040] like Figure 3 As shown in the figure, the rake angle of the tool tip radius is variable, including three rake angles, namely α, β and γ, and the degrees of the three rake angles are -3°, -2° and -3° respectively. The variable rake angle structure enables the tool to automatically adjust according to the changes in cutting conditions and change the distribution of cutting force. When the rake angle of the tool tip radius changes, the contact area and contact angle between the cutting edge and the material will also change accordingly, which will cause the distribution of cutting force on the cutting edge to change, thereby maintaining the best cutting state.

[0041] like Figure 3 As shown, the outer diameter of the cutting portion 2 is D, and the radius of the blade tip rounded edge 5 is R, satisfying 0.03D≤R≤0.2D. Therefore, the contact length between the blade tip rounded edge 5 and the cut material is short, and the cutting resistance is reduced, thereby preventing the blade tip from chipping.

[0042] like Figure 4 and Figure 5 As shown, the rake angle θ1 of the front cutting edge of the end edge is a negative value, and the degree of the rake angle θ1 satisfies -3°≤θ≤-5°, the back angle θ2 of the end edge is a positive value, and the degree of the back angle θ2 satisfies 8°≤θ2≤12°, the rake angle ε1 of the front cutting edge 401 of the peripheral edge is a negative value, and the degree of the rake angle ε1 satisfies -2°≤ε1≤-8°, the back angle ε2 of the peripheral edge is a positive value, and the degree of the back angle ε2 satisfies 10°≤ε2≤15°, which can make the cutting edge obtain higher strength and have a longer life when cutting high hardness materials.

[0043] like Figure 5 As shown, the core thickness diameter of the milling cutter in this embodiment is d, which satisfies d=0.7D, ensuring the overall strength of the tool and ensuring that the chips can be discharged smoothly. This helps to keep the cutting process smooth and prevents chips from accumulating on the tool or workpiece, thereby avoiding negative effects on processing quality and tool life.

[0044] like Figure 6 As shown, the end edge 3, the peripheral edge 4 and the tip radius edge 5 are set as blunt-shaped cutting edges with a blunt radius r of 8μm-12μm, which can reduce the interaction force, reduce the cutting heat and wear during the processing, make the cutting edge stronger, and thus extend the service life of the tool.

[0045] Further optimization is that the shank 1 and the cutting part 2 are made of nanocrystalline material, the tool is made of nanocrystalline WC material with a hardness of 93HRA and a cobalt content of 9%, which has high hardness and wear resistance, and the tool surface coating adopts a nano gradient coating. The coating material is a multilayer structure composed of titanium nitride, chromium nitride or nitrogen aluminum titanium, which has high hardness and high temperature stability.

[0046] Application Examples

[0047]

[0048]

[0049] This specific embodiment is only an explanation of the present invention, and it is not a limitation of the present invention. After reading this specification, those skilled in the art can make non-creative modifications to this embodiment as needed, but as long as it is within the scope of the claims of the present invention, it will be protected by the application law.

Claims

1. A high-hardness mold radius milling cutter, characterized in that: include: A milling cutter body, the milling cutter body comprising a shank (1) and a cutting portion (2) arranged at one end of the shank (1), the cutting portion (2) comprising a plurality of cutting edges and a spiral chip removal groove (8), the cutting edges comprising an end edge (3) arranged at the bottom of the cutting portion (2), a peripheral edge (4) arranged around the cutting portion, and a tool tip rounded edge (5) connecting the end edge (3) and the corresponding peripheral edge (4); The end blade (3) comprises a plurality of long teeth (6) and a plurality of short teeth (7); the blade tip rounded edge (5) is in an arc shape; and the blade tip rounded edge (5) is a variable rake angle structure; The end edge (3) comprises an end edge rake face (301), an end edge flank face (302), and an end edge blunt circle (303) for connecting the end edge rake face (301) and the end edge flank face (302); The peripheral blade (4) comprises a peripheral blade rake surface (401), a peripheral blade flank surface (402), and a peripheral blade blunt circle (403) for connecting the peripheral blade rake surface (401) and the peripheral blade flank surface (402); The rounded blade tip (5) comprises a rounded blade rake face (501), a rounded blade flank face (502), and a rounded blade blunt circle (503) for connecting the rounded blade rake face (501) and the rounded blade flank face (502); The end edge rake face (301), the peripheral edge rake face (401) and the tip rounded edge rake face (501) form a spiral chip removal groove (8).

2. A high hardness mold radius milling cutter according to claim 1, characterized in that: The end blade (3) comprises two long teeth (6) and two short teeth (7), and the long teeth (6) and the short teeth (7) are arranged at intervals.

3. A high hardness mold radius milling cutter according to claim 1, characterized in that: The outer diameter of the cutting portion (2) is D, and the radius of the blade tip rounded edge (5) is R, satisfying 0.03D≤R≤0.2D.

4. A high-hardness mold corner milling cutter according to claim 3, characterized in that: The core thickness diameter of the milling cutter body is d, which satisfies d=70%D.

5. The high-hardness mold radius milling cutter according to claim 1, characterized in that: The variable rake angle structure includes three rake angles, namely α, β and γ, and the degrees of the three rake angles are respectively -3°, -2° and -3°.

6. A high-hardness mold radius milling cutter according to claim 1, characterized in that: The front angle θ1 of the front cutting edge (301) is a negative value, satisfying -3°≤θ≤-5°, and the back angle θ2 of the end cutting edge is a positive value, satisfying 8°≤θ2≤12°.

7. The high-hardness mold radius milling cutter according to claim 1, characterized in that: The front angle ε1 of the circumferential blade rake surface (401) is a negative value, satisfying -2°≤ε1≤-8°, and the back angle ε2 of the circumferential blade (4) is a positive value, satisfying 10°≤ε2≤15°.

8. The high-hardness mold radius milling cutter according to claim 1, characterized in that: The radius of the end edge blunt circle (303), the radius of the peripheral edge blunt circle (403) and the radius of the rounded edge blunt circle (503) are all r, satisfying 6μm≤r≤12μm.

9. The high-hardness mold radius milling cutter according to claim 1, characterized in that: The cutting part (2) is provided with a coating, wherein the coating material is a multilayer structure composed of titanium nitride, chromium nitride or nitride aluminum titanium.

10. The high-hardness mold radius milling cutter according to claim 1, characterized in that: The tool handle (1) and the cutting part (2) are made of nanocrystalline material.

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