An elliptical corner ceramic end mill

Abstract

The present invention discloses an elliptical corner ceramic end mill, comprising: the shank part of the end mill is a cylinder, the radius of the cylinder is the tool radius, and the other end of the shank part is the cutting edge part. The cutting edge part includes a peripheral cutting edge part and an end cutting edge part. The rotating surface of the peripheral cutting edge part is tangentially connected to the shank part, and the rotating surface of the end cutting edge part is tangentially connected to the rotating surface of the peripheral cutting edge part. The elliptical corner design of the present invention reduces the main cutting edge angle of the tool, increases the strength at the elliptical corner, reduces the axial cutting force, reduces the vibration during the cutting process, reduces the probability of chipping of the ceramic tool during high-speed milling, and is more conducive to achieving high-speed and stable cutting; the elliptical corner design increases the effective cutting linear speed of the cutting edge, enabling the ceramic end mill to better machine difficult-to-machine materials such as superalloys; the elliptical corner design increases the material removal rate, can improve the machining efficiency, and improve the surface machining quality of the workpiece.

Description

Technical Field

[0001] The present invention belongs to the technical field of cutting tools, and particularly relates to an elliptical corner ceramic end mill. Background Art

[0002] Difficult-to-machine materials such as superalloys are widely used in many industrial fields such as aerospace, gas turbines, and nuclear power. However, they are not easy to cut on machine tools, often undergo chemical reactions with tool materials during the machining process, have high cutting temperatures, large cutting forces, rapid tool wear, low production efficiency, and poor surface quality. As a tool material, ceramics have excellent high-speed cutting properties such as heat resistance, wear resistance, and high strength. However, traditional corner milling cutters have poor vibration resistance and are prone to chipping in high-speed and high-temperature cutting environments.

[0003] Therefore, how to provide a ceramic end mill with strong vibration resistance and not prone to chipping in the environment of high-speed cutting of difficult-to-machine materials such as superalloys is one of the technical problems that need to be solved urgently in this field. Summary of the Invention

[0004] The purpose of the present invention is to provide an elliptical corner ceramic end mill to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: An elliptical corner ceramic end mill, comprising: The handle part of the end mill is a cylinder, the radius of the cylinder is the tool radius, and the other end of the handle part is the cutting edge part. The cutting edge part includes a peripheral cutting edge part and an end cutting edge part. The rotary surface of the peripheral cutting edge part is tangentially connected to the handle part, and the rotary surface of the end cutting edge part is tangentially connected to the rotary surface of the peripheral cutting edge part.

[0006] Preferably, there are multiple cutting edges on the cutting edge part. The cutting edges include end cutting edges and peripheral cutting edges. The end cutting edges are distributed on the rotary surface formed by rotating a quarter ellipse around the tool axis, and the peripheral cutting edges are distributed on the surface of the cylinder. The number of end cutting edges and peripheral cutting edges is the same, and they are respectively tangentially connected.

[0007] Preferably, the elliptical rotary surface equation of the end cutting edge part is:

[0008]

[0009] The tool rectangular coordinate system O-XYZ where the elliptical rotary surface is located is a spatial rectangular coordinate system, and the construction process is as follows: Taking the center of the bottom circle at the lowest end of the rotary surface of the end cutting edge part as the coordinate origin O, the Z-axis and the tool axis are collinear, and the positive direction of the Z-axis points from the origin O to the handle part (1). The X-axis direction is the starting position of the end cutting edge, the Y-axis is orthogonal to the X-axis and the Z-axis at the origin O, and the Y-axis direction follows the right-hand rule. Among them, X D , Y D and Z DThey are the coordinate values of the points on the elliptical rotating surface of the end cutting edge in the tool rectangular coordinate system O-XYZ. a is the length of the major semi-axis of the ellipse, b is the length of the minor semi-axis of the ellipse, R is the tool radius, and θ is the tool parameter. It is the angle between the radial line of any point on the elliptical rotating surface of the end cutting edge and the XOZ plane.

[0010] Preferably, the equation of the first end cutting edge curve on the cutting edge is:

[0011]

[0012] where β is the helix angle of the peripheral cutting edge, and X0, Y0, and Z0 are the coordinate values of the points on the end cutting edge curve in the tool rectangular coordinate system O-XYZ.

[0013] Preferably, the relationship among the length a of the major semi-axis of the ellipse, the length b of the minor semi-axis of the ellipse, the tool radius R, and the fillet radius r of the fillet milling cutter with the same radius in the rotating surface of the end cutting edge is: b ≤ a = r ≤ R.

[0014] Compared with the prior art, the technical effects and advantages of the present invention are as follows: For this elliptical angle ceramic end mill, through the described elliptical angle design, the main cutting edge angle is reduced, the strength at the elliptical angle is increased, the axial cutting force is reduced, the vibration during cutting is reduced, the probability of chipping of the ceramic tool during high-speed milling is reduced, it is more conducive to achieving high-speed and stable cutting, the tool life is improved, and the surface quality of the workpiece is better;

[0015] Through the design of the elliptical angle, the effective cutting linear speed of the cutting edge is increased, and the cutting efficiency of the tool is improved;

[0016] Through the design of the elliptical angle, compared with a fillet milling cutter with the same tool radius and a fillet radius r equal to the length a of the major semi-axis of the ellipse, the metal removal amount of the elliptical angle ceramic end mill is larger, thereby improving the machining efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of an elliptical angle ceramic end mill of the present invention;

[0018] Figure 2 It is a longitudinal sectional view of an elliptical angle ceramic end mill of the present invention;

[0019] Figure 3 It is a B-B cross-sectional view of the end cutting edge of an elliptical angle ceramic end mill of the present invention;

[0020] Figure 4 It is an A-A cross-sectional view of the peripheral cutting edge of an elliptical angle ceramic end mill of the present invention;

[0021] Figure 5Schematic diagram for comparing the machining residual height between an elliptical corner ceramic end mill and a round corner end mill of the present invention under the same machining step-over distance L;

[0022] Figure 6 Schematic diagram for constructing the right-angle coordinate system of a tool of an elliptical corner ceramic end mill of the present invention.

[0023] In the figure: 1. Tool shank part; 2. Cutting edge part; 3. Helix angle; 2-1. Peripheral edge part; 2-2. End edge part; 2-3. Cutting edge; 2-4. End edge; 2-5. Peripheral edge; 2-6. First flank face of peripheral edge; 2-7. Second flank face of peripheral edge; 2-8. Helical flute; 2-9. Rake face of peripheral edge. Specific embodiments

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0025] Please refer to Figures 1-6 , the present invention provides a technical solution: an elliptical corner ceramic end mill, on the cutting edge part 2 there are multiple cutting edges 2-3, the cutting edges 2-3 include end edges 2-4 and peripheral edges 2-5, the end edges 2-4 are distributed on the rotating surface formed by rotating a quarter ellipse around the tool axis, the peripheral edges (2-5) are distributed on the surface of the cylinder, and the number of end edges 2-4 and peripheral edges 2-5 is the same and they are respectively tangent and connected. The tool shank part 1 of the elliptical corner ceramic end mill is a cylinder, the cylinder radius is the tool radius, the cutting edge part 2 is located at the other end of the cylinder of the tool shank part 1, the cutting edge part includes a peripheral edge part 2-1 and an end edge part 2-2, and from one end to the other end of the cylinder are successively the end edge part 2-2, the peripheral edge part 2-1 and the tool shank part 1. There are multiple cutting edges 2-3 on the cutting edge part 2, the cutting edges 2-3 include end edges 2-4 and peripheral edges 2-5, the end edges 2-4 are on the rotating surface formed by rotating a quarter ellipse around the tool axis, the peripheral edges 2-5 are distributed on the surface of the cylinder, and they are respectively tangent and connected.

[0026] The overall length of the elliptical corner ceramic end mill is 60 - 160 mm, the tool radius is 2 - 10 mm, and the number of teeth is 2 - 6. It includes a shank part 1 and a cutting edge part 2. The shank part 1 and the cutting edge part 2 are integrally formed, and the material used is ceramic, which has high hardness and high strength. The first flank angle of the peripheral edge 2-5 is w1, the second flank angle of the peripheral edge 2-5 is w2, the rake angle of the peripheral edge 2-5 is r1, the first flank angle of the end edge 2-4 is v1, the second flank angle of the end edge 2-4 is v2, and the rake angle of the end edge 2-4 is r2. The first flank angle, the second flank angle, and the rake angle of the peripheral edge 2-5 and the end edge 2-4 are respectively the same. The value ranges of w1 and v1 are 6° - 25°, the value ranges of w2 and v2 are 10° - 30°, and the value ranges of r1 and r2 are -20° - 0°. The angle between the axis of the rotating surface of the peripheral edge part 2-1 and the tangent line L1 of the peripheral edge 2-5 is the helix angle 3, and the value range of the helix angle 3 is 30° - 45°.

[0027] In this embodiment, the equation of the rotating surface of the end edge part 2-2 is:

[0028]

[0029] where a is the length of the major semi-axis of the ellipse, b is the length of the minor semi-axis of the ellipse, R is the tool radius, X D , Y D and Z D are the coordinate values of the points on the elliptical rotating surface of the end edge part 2-2 in the tool rectangular coordinate system O-XYZ. θ is the tool parameter, is the angle between the radial line of any point on the elliptical rotating surface of the end edge part 2-2 and the XOZ plane.

[0030] In this embodiment, the curve equation of the end edge 2-4 is:

[0031]

[0032] where β is the helix angle 3 of the peripheral edge 2-5, and X0, Y0, and Z0 are the coordinate values of the points on the curve of the end edge 2-4 in the tool rectangular coordinate system O-XYZ.

[0033] The relationship among the length a of the major semi-axis of the ellipse, the length b of the minor semi-axis of the ellipse, the tool radius R, and the fillet radius r of the fillet end mill with the same radius in the rotating surface of the end edge part 2-2 is: b ≤ a = r ≤ R.

[0034] Combined with Figure 1 to illustrate this embodiment, the elliptical corner ceramic end mill described in this embodiment has an overall length of 75 mm, a tool radius of 5 mm, and the number of cutting edges 2-3 is 2. It includes 2 peripheral edges 2-5 and 2 end edges 2-4. The shank part 1 and the cutting edge part 2 are integrally formed.

[0035] Combined with Figures 1-4Regarding this embodiment, for the elliptical corner ceramic end mill described in this embodiment, the value of w1 is 8°, the value of w2 is 16°, and the value of r1 is -15°.

[0036] For the first flank angle w1 of the peripheral edge 2-5, it is taken as 8°; for the second flank angle w2 of the peripheral edge 2-5, it is taken as 16°; for the rake angle r1 of the peripheral edge 2-5, it is taken as -15°. For the first flank angle v1 of the end edge 2-4, it is taken as 8°; for the second flank angle v2 of the end edge 2-4, it is taken as 16°; for the rake angle r2 of the end edge 2-4, it is taken as -15°. The flank angles and rake angles of the peripheral edge 2-5 and the end edge 2-4 are respectively the same.

[0037] Combined with Figure 1 Regarding this embodiment, for the elliptical corner ceramic end mill described in this embodiment, the value of the helix angle 3 is 35°, which increases the chip evacuation space.

[0038] Combined with Figure 1 Regarding this embodiment, for the elliptical corner ceramic end mill described in this embodiment, two helical grooves 2-8 extending spirally along its axial direction are provided on the peripheral edge portion 2-1. The surface of the helical groove 2-8 facing the cutting rotation direction is the peripheral edge rake face 2-9. The peripheral edge rake face 2-9 intersects with the outer peripheral surface of the peripheral edge portion 2-1 to form the peripheral edge 2-5. The outer peripheral wall of the peripheral edge portion 2-1 connected to the peripheral edge 2-5 forms the first flank face 2-6 of the peripheral edge. Both the peripheral edge 2-5 and the end edge 2-4 are used for cutting work. The helical groove 2-8 is used to timely discharge chips during the operation of the end mill to ensure the normal operation of cutting.

[0039] It should be noted that this elliptical corner ceramic end mill is mainly used for rough machining and semi-finishing of workpieces.

[0040] In this embodiment, the width of the first flank face 2-6 of the peripheral edge is 0.5 mm, and the width of the second flank face 2-7 of the peripheral edge is 3 mm. The number of the helical grooves 2-8 is the same as the number of the cutting edges 2-3, both being two.

[0041] Combined with Figure 5 Regarding this embodiment, for the elliptical corner ceramic end mill described in this embodiment, compared with a corner milling cutter having the same tool radius and a fillet r equal to the length of the major semi-axis a of the ellipse, the metal removal amount of the elliptical corner ceramic end mill is larger, thereby improving the machining efficiency. 4 represents the longitudinal section line of the end edge portion rotating surface of the corner milling cutter, and 5 represents the longitudinal section line of the end edge portion rotating surface of the elliptical corner milling cutter. H1 represents the machining residual height of the corner milling cutter, and H2 represents the machining residual height of the elliptical corner ceramic end mill. Combined with Figure 5 It can be known that when the machining feed pitch L is the same, the machining residual height of the elliptical corner ceramic end mill is smaller, improving the machining surface quality of the workpiece.

[0042] Specifically, during use, when working, the elliptical corner ceramic end mill of the present invention can be installed in a three-axis linkage CNC milling machine or a five-axis linkage CNC milling machine for processing.

[0043] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An elliptical angle ceramic end mill, comprising: The shank portion (1) of the milling cutter is a cylinder, the radius of the cylinder is the radius of the tool, and the other end of the shank portion (1) is a blade portion (2), characterized in that: the blade portion (2) comprises a peripheral blade portion (2-1) and an end blade portion (2-2), the rotating surface of the peripheral blade portion (2-1) is tangentially connected to the shank portion (1), and the rotating surface of the end blade portion (2-2) is tangentially connected to the rotating surface of the peripheral blade portion (2-1); The blade portion (2) has a plurality of cutting edges (2-3), the cutting edges (2-3) comprising end edges (2-4) and peripheral edges (2-5), the end edges (2-4) being distributed on a revolving surface formed by rotating around the tool axis in a quarter ellipse, and the peripheral edges (2-5) being distributed on a cylindrical surface, the end edges (2-4) and peripheral edges (2-5) being the same in number and correspondingly connected tangent to each other; The equation of the elliptical revolution surface of the end blade portion (2-2) is: ; The tool rectangular coordinate system where the elliptical rotation surface is located O-XYZ The spatial rectangular coordinate system is constructed as follows: the center of the bottom circle of the rotating surface of the end blade (2-2) is taken as the origin of the coordinate system. O , Z The axis and the tool axis are collinear, Z The positive direction of the axis is from the origin O Point to the direction of the handle (1). X The axial direction is the starting position of the end blade. Y Axis and X Axis and Z Axis at origin O are orthogonal, and Y The axis direction follows the right-hand rule, where X D , Y D and Z D The point on the rotating surface of the end cutting edge (2-2) in the tool rectangular coordinate system O-XYZ The coordinate values ​​in a is the length of the major semi-axis of the ellipse, b is the length of the minor semi-axis of the ellipse, R is the tool radius, θ is the tool parameter, φ is the radial line and XOZ The angle between the faces.

2. The elliptical angle ceramic end mill according to claim 1, characterized in that: The curve equation of the first end edge (2-4) on the cutting edge (2-3) is: ; in β is the helix angle (3) of the peripheral edge (2-5), X 0, Y 0 and Z 0 is the point on the end edge (2-4) curve in the tool rectangular coordinate system O-XYZ The coordinate values ​​in .

3. The elliptical angle ceramic end mill according to claim 1, characterized in that: The length of the major semi-axis of the ellipse in the rotation surface of the end blade portion (2-2) a , the length of the minor semi-axis of the ellipse b , tool radius R The fillet radius of the corner milling cutter with the same radius r The relationship is: b ≤ a = r ≤ R .

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