PCBN (Polycrystalline Cubic Boron Nitride) miniature ball-end double-helix

Abstract

The utility model relates to a PCBN (Polycrystalline Cubic Boron Nitride) miniature ball-end double-spiral-edge 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; the ball head is provided with the double spiral blades, vibration and noise can be reduced, machining precision is high, the ball head is suitable for micro-cutting machining of complex curved surfaces of precision dies, and machining requirements of workpieces in complex shapes are met. And the ball head cutting edge adopts a variable tooth gap front angle, so that the distribution of cutting resistance can be effectively improved, local concentrated wear cannot be generated, and the durability of the tool is high. Compared with a straight groove structure, the spiral blade structure effectively reduces cutting force distribution at the cutting blade, and reduces cutting resistance. The cutting part is made of the PCBN composite material, so that the cutter has high hardness, high wear resistance, better thermal conductivity and lower friction coefficient, and also has excellent chemical stability, thermal stability and processing red hardness.

Description

TECHNICAL FIELD

[0001] The utility model relates to a milling cutter technical field especially is related to a PCBN micro -type ball head double helical edge milling cutter. BACKGROUND

[0002] With the progress of science and technology, the manufacturing field of aerospace, automobile and the like develops rapidly, so that high-hardness, high-strength, corrosion-resistant steel materials are widely used.

[0003] As an important part of the automobile, the automobile headlamp requires high machining precision of the die, which is mainly due to the fact that the headlamp not only requires an attractive appearance, but also requires high precision and excellent optical performance. The automobile headlamp die usually contains complex curved surface structures such as a reflector polyhedron, and the machining precision of these curved surfaces directly affects the optical performance of the headlamp.

[0004] The automobile headlamp die usually adopts high-hardness die steel, and the hardness after quenching can reach 50-65HRC, which belongs to a typical difficult-to-machine material. The surface roughness of the die usually needs to be controlled within the range of Ra0.05-0.10μm to meet the high smoothness requirement of the headlamp. At the same time, higher requirements are also put forward for the cutter. The diameter of the micro milling cutter is usually very small, which makes the cutter prone to wear and breakage during machining. Cutter wear will directly affect the machining precision and surface quality, and may even lead to machining failure.

[0005] Therefore, there is an urgent need for a PCBN micro ball head double helical edge milling cutter to adapt to the milling and grinding of die steel. SUMMARY

[0006] In order to solve the problems existing in the prior art, the utility model provides a PCBN micro ball head double helical edge milling cutter, which adopts the following technical scheme: a cutter handle and a cutting part arranged at one end of the cutter handle are included, the cutting part includes a plurality of cutting edges, the cutting edges include a peripheral edge arranged on the ring side of the cutting part and a ball head cutting edge arranged on the end part of the cutting part, the ball head cutting edge is provided with a variable tooth gap rake angle, and the cutting part is made of PCBN composite material.

[0007] It is further characterized in that,

[0008] The cutting edge is provided with two.

[0009] Two helical chip removal grooves are arranged on the cutting part along the outer periphery, and the two helical chip removal grooves 5 extend helically from the ring side of the cutting part to the end part of the cutting part.

[0010] The cutting part is welded on the cutter handle by high-frequency induction brazing.

[0011] The peripheral edge is provided with a clearance angle, and the clearance angle is provided with two.

[0012] Two said ball head cutting edges are oppositely arranged.

[0013] The angles of the variable tooth gap rake angles are -3 degrees, -2 degrees and -3 degrees in sequence.

[0014] The diameter of the end of the tool shank close to the cutting part is smaller than the diameter of the end of the tool shank far from the cutting part.

[0015] The above structure of the utility model can achieve the following beneficial effects:

[0016] The double helical edges of the ball head can reduce vibration and noise, and the machining precision is high, and the ball head is suitable for precision mold complex curved surface micro cutting, and can meet the machining requirements of complex shape workpieces. The ball head cutting edge adopts a variable tooth gap rake angle, which can effectively improve the distribution of cutting resistance, and will not cause local concentrated wear, and the tool has high durability. The cutting part is made of PCBN composite material, so that the tool has high hardness, high wear resistance, good heat conductivity, low friction coefficient, excellent chemical stability, thermal stability and machining red hardness. In the machining of high-hardness precision molds (HRC50-65), the tool can replace the carbide tool, improve the tool life and reduce the tool cost, and obtain high surface machining quality, so as to adapt to the machining of small and complex curved surfaces of the mold. Moreover, the ball head cutting edge has multiple rake angles, forming a multi-tooth gap rake angle structure, which can effectively improve the distribution of cutting resistance, and the process of cutting in and cutting out is relatively stable. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a schematic diagram of the overall structure of the embodiment of the application;

[0018] Figure 2 is a schematic diagram of the structure of the end of the cutting part in the embodiment of the application;

[0019] Figure 3 is a structure sectional view of the ball head cutting edge in the embodiment of the application.

[0020] Reference signs: 1, tool shank; 2, cutting part; 3, peripheral edge; 4, ball head cutting edge; 5, helical chip removal groove; 6, ball head blade part. DETAILED DESCRIPTION

[0021] In order for those skilled in the art to better understand the utility model scheme, the technical solutions in the embodiments of the utility model will be clearly and completely described below in combination with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only a part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor should belong to the protection scope of the utility model.

[0022] It is to be understood that the terms "including", "comprising", "having" and "with" used in the specification and the above claims are used in the sense of "including" and are not used in the sense of "consisting only of or "consisting exclusively of the listed steps or units, and that, consequently, these terms specifically permit the inclusion of additional steps or units that are not specifically recited.

[0023] The utility model is further explained in detail below. Figures 1-3 The utility model is further explained in detail below.

[0024] Refer to Figures 1-3 A PCBN micro ball head double helix blade milling cutter, including handle 1 and the cutting part 2 of setting in handle 1 one end, cutting part 2 includes several cutting edges, cutting edge includes the peripheral edge 3 of setting in the ring side of cutting part 2 and the ball head cutting edge 4 of setting in the end of cutting part 2, ball head cutting edge 4 is equipped with multiple rake angles, cutting part 2 adopts PCBN (polycrystalline cubic boron nitride) composite material and is made, ball head blade part 6 (is made of several ball head cutting edges 4) sets double helix blade, can reduce vibration and noise, and the machining precision is high, is applicable to the precision mould complex curved surface micro cutting processing, satisfies the machining demand of complex shape workpiece. Ball head cutting edge 4 adopts the variable clearance rake angle, can effectively improve the distribution of cutting resistance, will not produce local concentrated wear, and the tool durability is high. Cutting part 2 adopts PCBN composite material, so that the tool has high hardness, high wear resistance, better thermal conductivity, lower friction coefficient, and also has excellent chemical stability, thermal stability and machining red hardness, processes high hardness, high strength, corrosion resistance steel and obtains higher surface processing quality.

[0025] Further optimization is, as Figure 1 Shown, cutting edge is provided with two in the embodiment, that is to say, ball head cutting edge 4 and peripheral edge 3 are provided with two, two ball head cutting edges 4 are oppositely arranged, and ball head blade part 6 is composed of two ball head cutting edges 4, adopts double helix blade structure design, and the cutting component of three directions is small when helix blade processes, and cutting is stable.

[0026] As Figure 1 Shown, two helical chip removal grooves 5 are formed on the cutting part 2 along the outer periphery, and the two chip removal grooves 5 extend helically from the ring side of the cutting part 2 to the end of the cutting part 2. The helical chip removal grooves 5 cooperate with the different blade rake angles on the ball head cutting edges 4 to smoothly discharge the chips along the direction of the cutting edges, effectively prevent the blade from breaking, and reduce the interference of the chips with the workpiece machining surface.

[0027] Further optimization is that the cutting part 2 is welded on the handle 1 by high-frequency induction brazing, and the cutting part 2 and the handle 1 are welded together by high-frequency induction brazing technology. During the welding process, infrared detection is used for accurate detection of the welding temperature.

[0028] Further optimization is that, as shown in Figure 2 In order to improve the strength of the ball head cutting edge 3, the size of the ball head tooth gap arc is controlled, wherein the maximum arc R is 0.03mm, and the strength of the ball head cutting edge is improved.

[0029] Further optimization is that, as shown in Figure 3 In order to reduce the friction between the ball head cutting edge 3 and the machined surface, the peripheral edge 3 is provided with two clearance angles, one of which is δ and the angle is set to 12°-18° (for example, 12°, 14° or 18°, etc.), and the other is ε and the angle is set to 25°-30° (for example, 25°, 28° or 30°, etc.).

[0030] As shown in Figure 3 The variable tooth gap rake angle in the embodiment is specifically: there are three rake angles at the tooth gap of the ball head milling cutter, which are the rake angles at the ball head 0°, the ball head 45° and the ball head 90°, and the angles are-3° (α),-2° (β) and-3° (γ) in turn.

[0031] Further optimization is that the cutting part 2 is ground by coarse grinding wheel, medium grinding wheel and fine grinding wheel, which reduces the defects of the two ball head cutting edges 4 and the roughness of the two peripheral edges 3, the grinding wheel dressing frequency is 70 dressing 1 time, and the surface burning and damage of the tool caused by the blockage of the grinding wheel are avoided.

[0032] Further optimization is that the diameter of the ball head cutting tool in the embodiment is preferably D0.1-D1, and the machinable high-hardness die steel hardness is 50HRC-65HRC.

[0033] Further optimization is that, in order to further improve the convenience of machining, the diameter of the end of the shank 1 close to the cutting part 2 is smaller than the diameter of the end away from the cutting part 2, so as to reduce the interference of the shank 1 in the machining process as much as possible.

[0034] In summary, the cutting part 2 is made of PCBN composite material, the ball head blade part 6 first contacts the machined surface of the workpiece to play the role of centering, there is no sharp corner part on the blade, which will not cause local concentrated wear, the tool has high durability, can machine complex curved surface, and the cutting part 2 is made of PCBN composite material, so that the tool has high hardness, high wear resistance, good heat conductivity, low friction coefficient, and also has excellent chemical stability, thermal stability and machining red hardness, can realize the replacement of hard alloy cutting tool in high-hardness precision die (HRC50-65) machining, improve the tool life and reduce the tool cost, and obtain higher surface machining quality, so as to adapt to the machining of small and complex curved surface of the die. The ball head cutting edge 4 has multiple rake angles, forming a multi-tooth gap rake angle structure, which can effectively improve the distribution of cutting resistance, and the process of cutting in and cutting out is relatively stable.

[0035] The embodiments are only used for explaining the present application, and are not used for limiting the present application, and the person skilled in the art can make the modification of the embodiments without the creative contribution according to the need after reading the description, and as long as the modification is within the scope of the claims of the present application, it is protected by the patent law.

Claims

1. A PCBN micro ball-end double-helical edge milling cutter, characterized in that: The invention comprises a tool holder (1) and a cutting portion (2) arranged at one end of the tool holder (1); the cutting portion (2) comprises a plurality of cutting edges, the cutting edges comprising a peripheral edge (3) arranged on the annular side of the cutting portion (2) and a ball-end cutting edge (4) arranged at the end of the cutting portion (2); the ball-end cutting edge (4) is provided with a variable tooth clearance rake angle; and the cutting portion (2) is made of PCBN composite material.

2. The PCBN micro ball-end double-helical edge milling cutter according to claim 1, characterized in that: There are two cutting edges.

3. The PCBN micro ball-end double-helical edge milling cutter according to claim 2, characterized in that: Two spiral chip removal grooves (5) are provided along the outer periphery of the cutting portion (2), and the two spiral chip removal grooves (5) spirally extend from the annular side of the cutting portion (2) to the end of the cutting portion (2).

4. The PCBN micro ball-end double-helical edge milling cutter according to claim 1, characterized in that: The cutting portion (2) is welded to the shank (1) by high-frequency induction brazing.

5. The PCBN micro ball-end double-helical edge milling cutter according to claim 1, characterized in that: The peripheral blade (3) is provided with a back angle, and there are two back angles.

6. The PCBN micro ball-end double-helical edge milling cutter according to claim 2, characterized in that: The two ball-end cutting edges (4) are arranged opposite to each other.

7. The PCBN micro ball-end double-helical edge milling cutter according to claim 1, characterized in that: The angles of the variable tooth backlash rake angle are -3°, -2° and -3° respectively.

8. The PCBN micro ball-end double-helical edge milling cutter according to claim 1, characterized in that: The diameter of the end of the shank (1) close to the cutting portion (2) is smaller than the diameter of the end away from the cutting portion (2).

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