Double-sided, indexable cutting inserts with high ramping performance, and cutting tools for cutting inserts.
The double-sided cutting insert with a recessed area enhances milling and ramping performance by increasing the peripheral relief angle, addressing the limitations of conventional inserts with shallow ramping capabilities.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- KENNAMETAL INC
- Filing Date
- 2024-03-26
- Publication Date
- 2026-04-10
AI Technical Summary
Conventional indexable milling inserts have limited ramping performance, capable only of shallow angle operations, necessitating an improved cutting insert that can effectively perform both milling and ramping operations.
A double-sided cutting insert with a recessed area adjacent to the main cutting edge, featuring a radius that increases the peripheral relief angle, minimizing friction and enhancing ramping performance.
The cutting insert achieves high ramping angles and reduces rubbing or friction during machining operations, providing improved milling and ramping capabilities.
Smart Images
Figure 2026510988000001_ABST
Abstract
Description
Background Art
[0001] The present invention relates to a cutting insert for cutting operations, and more particularly to a double-sided and indexable cutting insert capable of performing milling operations and ramping operations.
[0002] A milling cutter for performing machining operations on a metal workpiece is well known in the prior art. Such cutters typically comprise a cylindrical or disc-shaped body removably connectable to a rotary drive shaft. The cutting insert is attached around the outer periphery of the cutter body to perform a series of metal-removing cuts on the workpiece.
[0003] Conventional indexable milling inserts that claim ramping capabilities can perform ramping operations only at very small angles or shallow angles. As a result, conventional indexable milling inserts that claim ramping performance have very low ramping performance.
[0004] Therefore, there is a need for an improved cutting insert that can properly perform both milling and ramping cutting operations.
Summary of the Invention
[0005] The problem of a double-sided cutting insert that cannot properly perform both milling and ramping cutting operations is solved by providing a recessed area on the upper or bottom surface adjacent to a portion of the main cutting edge of the cutting insert, the recessed area defining a radius that increases the peripheral relief angle and minimizes rubbing or friction during the ramping cutting operation.
[0006] In one embodiment, a double-sided, indexable cutting insert for a milling cutter comprises a first surface including a central planar seating surface, a second surface opposite the first surface, a first side surface including a central planar seating surface perpendicular to the first side surface, and a first cutting edge defined at the intersection of the first surface and the first side surface. The first cutting edge is substantially V-shaped and includes a first cutting edge portion extending radially outward with respect to the horizontal axis of the cutting insert, a second cutting edge portion extending radially outward with respect to the horizontal axis, and a third cutting edge portion extending between the first and second cutting edge portions and substantially parallel to the horizontal axis.
[0007] In another embodiment, the milling cutter comprises a shank and an upper part having an insert pocket. The insert pocket includes a bottom seating surface, a radial seating surface, and an axial seating surface. A cutting insert is mounted in the insert pocket. The cutting insert includes a first surface including a central planar seating surface, a second surface opposite the first surface, a first side surface including a central planar seating surface perpendicular to the first side surface, and a first cutting edge defined at the intersection of the first surface and the first side surface. The first cutting edge is substantially V-shaped and includes a first cutting edge portion extending radially outward with respect to the horizontal axis of the cutting insert, a second cutting edge portion extending radially outward with respect to the horizontal axis, and a third cutting edge portion extending between the first and second cutting edge portions and substantially parallel to the horizontal axis. Brief explanation of the drawing
[0008] While various embodiments of the present invention are illustrated, the specific embodiments shown should not be construed as limiting the scope of the claims. It is anticipated that various changes and modifications may be made without departing from the scope of the present invention. [Brief explanation of the drawing]
[0009] [Figure 1] This is a perspective view of a cutting insert, such as a milling insert, according to an embodiment of the present disclosure. [Figure 2] This is another perspective view of the cutting insert shown in Figure 1. [Figure 3] Figure 1 is a front view of the cutting insert (the rear view is the same as the front view). [Figure 4] Figure 1 is a side view of the cutting insert. [Figure 5] Figure 1 is an end view of the cutting insert. [Figure 6] This is a cross-sectional view of the cutting insert taken along line 6-6 in Figure 3. [Figure 7] This is a cross-sectional view of a cutting insert taken along line 7-7 in Figure 3. [Figure 8] This is a perspective view of a milling cutter according to an embodiment of the present invention, with the cutting insert not installed in the pocket for clarity. [Figure 9] Figure 8 is an end view of the milling cutter with the cutting insert shown in Figure 1 attached to the pocket. [Modes for carrying out the invention]
[0010] Referring to the drawings, similar reference letters represent similar elements, and Figures 1-5 generally show a cutting insert 10 including a first surface 12, a second surface 14 opposite the first surface 12, and sides 16, 18, 20, and 22. Sides 16, 18, 20, and 22 serve as seating surfaces when the cutting insert 10 is mounted on a cutting tool such as a milling cutter, as described below. The double-sided cutting insert 10 can perform both milling and ramping operations at high ramping angles.
[0011] It should be noted that the cutting insert 10 is a double-sided insert in which the first surface 12 is substantially identical to the second surface 14. Therefore, for brevity, only the first surface 12 may be described below. As is known in the art, when installed in a tool holder (not shown), the first surface 12 may be the top surface and the second surface may be the bottom surface, and vice versa. The cutting insert 10 includes a central longitudinal axis 11 (Z-axis), a second axis 13 (Y-axis) perpendicular to the central longitudinal axis 11, and a third axis 15 (X-axis) perpendicular to both the central longitudinal axis 11 and the second axis 13. It should also be noted that the central planar seating surface 17 of the first surface 12 (and the second surface 14) forms an angle 19 of approximately 90 degrees (i.e., orthogonal) with respect to each of the four sides 16, 18, 20, and 22.
[0012] Throughout this specification and the claims, any approximate terms used herein may be applied to modify any quantitative expression that may change acceptablely without altering the fundamental function to which it relates. Thus, values modified by terms such as “about,” “approximately,” and “substantially” are not limited to the exact values specified. In at least some cases, approximate terms may correspond to the precision of an instrument used to measure a value. Herein, and throughout this specification and the claims, scope limitations may be combined and / or interchangeable, and such scopes include all partial scopes specified and contained therein, unless otherwise indicated by context or wording.
[0013] Throughout the text and claims, the use of the word “about” in relation to a range of values (e.g., “about 22–35% by weight”) is intended to modify both the stated high and low values and reflect the variability associated with measurement, significant numerical values, and interchangeability, so as all will be understood by those skilled in the art to whom the invention relates.
[0014] For the purposes of this specification (except for the examples of operation), unless otherwise indicated, all numbers expressing quantities and ranges of components, process conditions, etc., should be understood in all cases to be modified by the term “approximately.” Accordingly, the numerical parameters described herein and in the appended claims are approximations that may vary depending on the desired results to be obtained by the invention, unless otherwise indicated. At a minimum, and not as an attempt to limit the application of the doctrine of equivalents to the claims, each numerical parameter should be interpreted at least in light of the number of significant figures reported and by applying ordinary rounding techniques. Furthermore, the singular forms “a,” “an,” and “the” used herein and in the appended claims are intended to include multiple referents unless explicitly and clearly limited to a single referent.
[0015] Although the numerical ranges and parameters describing the broad scope of the present invention are approximations, the numerical values described in specific embodiments are reported as accurately as possible. However, any numerical value inherently includes a certain error that inevitably arises from the standard deviation found in each of those test measurements (including the standard deviation found in the measuring instrument). Naturally, any numerical range described herein is intended to include all subranges contained therein. For example, the range "1 to 10" is intended to include all subranges between the stated minimum value of 1 and the stated maximum value of 10, and all subranges including the stated minimum value of 1 and the stated maximum value of 10, i.e., ranges having a minimum value of 1 or more and a maximum value of 10 or less. Since the disclosed numerical ranges are continuous, they include all values between the minimum and maximum values. Unless otherwise expressly indicated, the various numerical ranges specified in this application are approximations.
[0016] In the following specification and claims, several terms having the following meanings are referenced.
[0017] The singular forms "a", "an", and "the" include plural referents unless the context clearly indicates otherwise.
[0018] "Optional" or "optionally" means that the event or situation described thereafter may or may not occur, and that the description includes both the case where the event occurs and the case where it does not occur.
[0019] As used herein, the peripheral relief angle is the angle between the relief face and the radius measured in a plane perpendicular to the central axis of the milling cutter. The peripheral relief angle is important in determining the sharpness and strength of the cutting edge.
[0020] As used herein, the axial relief angle is the angle between the cutting edge and the central axis of the milling cutter. This angle affects the face milling process in several ways. It directs the chip flow and affects the strength of the cutting edge. [[ID=十三]]
[0021] As used herein, angle A starts from the peripheral relief angle and is the angle to the highest or forward region of the cutting insert. Angle A passes through the central axis of the milling cutter.
[0022] As used herein, angle B is a ramping angle starting from the highest or forward region of the cutting insert, or the intersection between the radius for ramping and the facet face. Angle B may be parallel to angle A, or may be equal to about 0 degrees to about 90 degrees. Angle B passes through the central axis of the milling cutter or passes below the central axis of the milling cutter.
[0023] The cutting insert 10 includes a first cutting edge 24 at the intersection between the side surface 16 and the first surface 12, and a second cutting edge 26 at the intersection between the side surface 18 and the first surface 12. Similarly, the cutting insert 10 includes a third cutting edge 28 at the intersection between the side surface 16 and the second surface 14, and a fourth cutting edge 30 at the intersection between the side surface 18 and the second surface 14 (not visible in FIG. 1). Thus, the double-sided usable cutting insert 10 includes a total of four cutting edges 24, 26, 28, and 30.
[0024] As shown in FIG. 2, each of the cutting edges 24, 26, 28, 30 is substantially V-shaped. For example, the first cutting edge 24 includes a first cutting edge portion 24a, a second cutting edge portion 24b, and a third cutting edge portion 24c disposed on the horizontal axis (i.e., the y-axis) and between the first main cutting edge portion 24a and the second main cutting edge portion 24b. In one embodiment, the third cutting edge portion 24c is centered on the central longitudinal axis (i.e., the y-axis). Since all the cutting edges 24, 26, 28, 30 are substantially the same, only the cutting edge 24 will be described herein for simplicity. As shown in FIG. 2, the first cutting edge portion 24a is located higher than the central plane seat surface 17 and acts as the main cutting edge during the machining operation, while the second cutting edge portion 24b is noted to be located lower than the central plane seat surface 17.
[0025] Each of the first cutting edge portion 24a, the second cutting edge portion 24b, and the third cutting edge portion 24c may be either planar or arcuate (i.e., curved). For example, in one embodiment, the first cutting edge portion 24a is substantially planar and forms an angle 32 with respect to the horizontal axis (i.e., the x-axis). The angle 32 can be from about 0.1 degrees to about 30 degrees. Similarly, the second cutting edge portion 24b is substantially planar and forms an angle 34 with respect to the horizontal axis. The angle 34 may be approximately equal to or different from the angle 32. In this embodiment, the third cutting edge portion is substantially planar and substantially parallel to the horizontal axis (i.e., the x-axis) 15.
[0026] In another embodiment, the first cutting edge portion 24a is arc-shaped or curved with a radius R1 of about IC / 2 to about 10 × IC, where IC is the inscribed circle of the cutting insert 10. Similarly, the second cutting edge portion 24b is arc-shaped or curved with a radius R2 of about IC / 2 to about 10 × IC. Radius R1 may be approximately equal to or different from radius R2. In this embodiment, the third cutting edge portion is formed with a radius R3 of about 0.05 mm to about 600 mm.
[0027] The third cutting edge portion 24c may also be planar or arc-shaped. The third cutting edge portion 24c provides excellent surface finish during machining of a workpiece (not shown). In one embodiment, the third cutting edge portion 24c has a width W of about 0.0 mm to about 10.0 mm. In other words, the first cutting edge 24 may include only the first cutting edge portion 24a and the second cutting edge portion 24b.
[0028] In the illustrated embodiment, corner radius 32 connects sides 16 and 20, corner radius 34 connects sides 18 and 20, corner radius 36 connects sides 16 and 22, and corner radius 38 connects sides 18 and 22.
[0029] The side surface 16 includes a faceted surface 40 extending radially outward from the corner radius 32, a faceted surface 42 extending radially outward from the corner radius 36, and a faceted surface 44 extending between faceted surface 40 and faceted surface 42. Faceted surfaces 40, 42, and 44 extend completely between the first surface 12 and the second surface 14.
[0030] If the cutting edges 24a, 24b, and 24c are substantially planar, then the facet surfaces 40, 42, and 44 are substantially planar. In this case, as can be seen in Figure 3, note that the planar facet surface 44 is substantially parallel to the horizontal axis 15 (i.e., the x-axis). If the cutting edges 24a, 24b, and 24c are arc-shaped or curved with radii R1, R2, and R3, respectively, then the facet surfaces 40, 42, and 44 are also arc-shaped or curved.
[0031] Naturally, the cutting insert 10 is mirror-symmetric about both horizontal axes 13, 15 (i.e., the y-axis and the x-axis). Although not visible in Figures 1 and 2, the side surface 18 of the cutting insert 10 includes a facet surface 42 extending radially outward from the corner radius 34, a facet surface 40 extending radially outward from the corner radius 38, and a facet surface 44 extending between facet surfaces 40, 42 and substantially parallel to the horizontal axis (i.e., the x-axis).
[0032] Side surface 20 includes a planar seating surface 46 extending from the corner radius 32, a planar seating surface 48 extending from the corner radius 34, and a planar recessed surface 50 between the planar seating surfaces 46 and 48. The planar recessed surface 50 is radially inward relative to the planar seating surfaces 46 and 48, as shown in Figure 3. Similarly, side surface 22 includes a planar seating surface 52 extending from the corner radius 36, a planar seating surface 54 extending from the corner radius 38, and a planar recessed surface 56 between the planar seating surfaces 52 and 54. The planar recessed surface 56 is radially inward relative to the planar seating surfaces 52 and 54. The planar seating surfaces 46 and 48 provide two contact points and add radial stability to the cutting insert 10 when it is mounted in the insert pocket.
[0033] The first surface 12 of the cutting insert 10 includes a central planar seating surface 17. The first surface 12 also includes a rake face 58 adjacent to the first cutting edge portion 24a and a chip breaker 60 adjacent to the rake face 58, which helps to remove chips during cutting operations such as milling. In the illustrated embodiment, the chip breaker 60 has one or more faceted surfaces 60a, 60b, 60c. Naturally, the first surface 12 also includes a rake face 62 adjacent to the first cutting edge portion 26a and a chip breaker 64 having one or more faceted surfaces 64a, 64b, 64c located diagonally opposite the rake face 58 and the chip breaker 60.
[0034] In addition, the first surface 12 includes a recessed area 66 adjacent to the second cutting edge portion 24b to assist in the removal of chips during cutting operations such as ramping. As shown in Figures 1 and 2, the recessed area 66 forms the second cutting edge portion 24b with a radius R. The radius R can be in the range of approximately 0.5 mm to approximately 20 mm.
[0035] In the illustrated embodiment, the radius R is smooth and continuous. However, it will be understood that the radius R may be formed by a facet surface 40 having a plurality of small planar facet surfaces. The recessed area 66 also provides clearance during cutting operations. In the illustrated embodiment, the recessed area 66 is substantially oval-shaped. However, it will be understood that the present invention is not limited by the shape of the recessed area 66 and may be carried out in other shapes such as elliptical, circular, etc. The recessed area 66 includes a chip breaker 68 to provide additional assistance for chip evacuation. Similarly, the first surface 12 includes a recessed area 70 located diagonally opposite the recessed area 66 having a chip breaker 72.
[0036] Naturally, the first surface 12 and the second surface 14 of the cutting insert 10 are mirror symmetric. Thus, although not visible in Figures 1 and 2, the second surface 14 also includes a central planar seating surface 17, rake faces 58, 62, chip breakers 60, 64, and recessed areas 66, 70 having chip breakers 68, 72. The countersunk hole 74 extends entirely between the first surface 12 and the second surface 14.
[0037] Referring here to Figures 8 and 9, a milling cutter 100 capable of receiving the cutting insert 10 of the present invention is shown. Generally, the milling cutter 100 includes a shank 102, an upper part 104, and a transition surface 106 between the shank 102 and the upper part 104. The cutter 100 is preferably made from a heat-treated steel such as H13 tool steel, or other material known to those skilled in the art. The specific material used will vary as a result of the desired design characteristics of the cutter 100. The cutter 100 rotates around a central axis 108. The cutter 100 also includes an insert pocket formed at the tip of the upper part 104 of the cutter 100, generally shown as 110. As shown in Figure 6, the insert pocket 110 includes a bottom seating surface 112, a radial seating surface 116, and an axial seating surface 114. Thus, the cutting insert 10 is attached to the pocket 110 at three contact points.
[0038] In the illustrated embodiment, the milling cutter 100 can accommodate four cutting inserts 10 in each insert pocket 110. However, it will be understood that the milling cutter 100 is not limited by the number of indexable cutting inserts 10 that can be fitted into the insert pockets 110, and the present invention can be carried out using any desired number of cutting inserts, within the limits limited only by the physical limitations of the material properties of the milling cutter. For example, the milling cutter may have two, three, five, six, seven, eight, or more insert pockets.
[0039] As shown in Figure 9, each cutting insert 10 is mounted in its respective pocket 110 with an outer rake angle 118 of approximately 0 to 45 degrees. In addition, the angle A provided by the radius R of the second cutting edge portion 24b is the angle from the outer rake angle 118 to the region of highest position in front of the cutting insert 10, passing through the central axis 108 of the milling cutter 100. Angle A provides the cutting insert 10 with a maximum ramping angle equal to the outer rake angle 118 plus angle A, before the cutting insert 10 begins to contact the workpiece (not shown). Angle A can range from approximately 0 to approximately 90 degrees.
[0040] Furthermore, angle B is the ramping angle that starts from the highest point in front of the cutting insert 10, passing through (i.e., parallel to angle A) the central axis 108 of the milling cutter 100, or passing below the central axis 108, as shown in Figure 9. Angle B can be approximately 0 degrees to approximately 90 degrees.
[0041] As described above, the cutting insert 10 of this disclosure provides a method for resolving abrasion or friction to a double-sided cutting insert during machining operations.
[0042] The patents and other documents specified herein are incorporated herein by reference. Other embodiments of the invention will become apparent to those skilled in the art from the examination herein or from the practice of the invention disclosed herein. This specification and the examples are illustrative and not intended to limit the scope of the invention. The true scope and spirit of the invention are set forth by the following claims.
Claims
1. A double-sided, indexable cutting insert (10) for a milling cutter (100), A first surface (12) including a central planar seating surface (17), The second surface (14) opposite to the first surface (12), A first side surface (16) including a central planar seating surface (17) perpendicular to the first side surface (16), wherein the first side surface (16) is substantially perpendicular to both the first surface (12) and the second surface (14), It comprises a first cutting edge (24) defined at the intersection between the first surface (12) and the first side surface (16), The first cutting edge (24) is substantially V-shaped and includes a first cutting edge portion (24a) extending radially outward with respect to the horizontal axis (15) of the cutting insert (10), a second cutting edge portion (24b) extending radially outward with respect to the horizontal axis (15), and a third cutting edge portion (24c) extending between the first cutting edge portion (24a) and the second cutting edge portion (24b) and substantially parallel to the horizontal axis (15). A double-sided, indexable cutting insert (10) for a milling cutter (100), wherein the first cutting edge portion (24a) is used during milling operations and the second cutting edge portion (24b) is used during ramping operations.
2. A double-sided, indexable cutting insert (10) for a milling cutter (100) according to claim 1, wherein the first cutting edge portion (24a), the second cutting edge portion (24b), and the third cutting edge portion (24c) are substantially planar.
3. A double-sided, indexable cutting insert (10) for a milling cutter (100) according to claim 2, wherein both the first cutting edge portion (24a) and the second cutting edge portion (24b) extend radially outward at an angle (32) of approximately 0.1 degrees to approximately 30 degrees with respect to the horizontal axis (15).
4. A double-sided, indexable cutting insert (10) for a milling cutter (100) according to claim 1, wherein the first cutting edge portion (24a), the second cutting edge portion (24b), and the third cutting edge portion (24c) are arc-shaped or curved.
5. A double-sided, indexable cutting insert (10) for a milling cutter (100) according to claim 4, wherein the first cutting edge portion (24a) is formed with a radius (R1) and the second cutting edge portion (24b) is formed with a radius (R2).
6. A double-sided, indexable cutting insert (10) for a milling cutter (100) according to claim 1, further comprising a second side (18) opposite to the first side (16), a third side (20), and a fourth side (22) opposite to the third side (20).
7. A double-sided, indexable cutting insert (10) for a milling cutter according to claim 6, further comprising a second cutting edge (26) defined at the intersection between the first surface (12) and the second side surface (18).
8. The second cutting edge (26) is substantially V-shaped and includes a first cutting edge portion (26a) extending radially outward with respect to a horizontal axis (15), a second cutting edge portion (26b) extending radially outward with respect to the horizontal axis (15), and a third cutting edge portion (26c) extending substantially parallel to the horizontal axis (15) between the first cutting edge portion (26a) and the second cutting edge portion (26b), wherein the double-sided, indexable cutting insert (10) for a milling cutter (100) according to claim 7.
9. A double-sided, indexable cutting insert (10) for a milling cutter (100) according to claim 8, wherein the first cutting edge portion (26a), the second cutting edge portion (26b), and the third cutting edge portion (26c) of the second cutting edge (26) are substantially planar.
10. The first cutting edge portion (26a) of the second cutting edge (26) extends radially outward at an angle (32) of about 0.1 degrees to about 30 degrees with respect to the horizontal axis (15), and the second cutting edge portion (26b) of the second cutting edge (26) extends radially outward at an angle (34) of about 0.1 degrees to about 30 degrees with respect to the horizontal axis (15), wherein the double-sided indexable cutting insert (10) for a milling cutter (100) according to claim 9.
11. A double-sided, indexable cutting insert (10) for a milling cutter (100) according to claim 1, wherein the first surface (12) includes a recessed area (66) adjacent to the second cutting edge portion (24b) to help discharge chips during cutting.
12. The double-sided, indexable cutting insert (10) for a milling cutter (100) according to claim 11, wherein the recessed region (66) includes a chip breaker (68).
13. The recessed region (66) forms the second cutting edge portion (24b) with a radius (R) in the double-sided, indexable cutting insert (10) for a milling cutter (100) according to claim 12.
14. A double-sided, indexable cutting insert (10) for a milling cutter (100) according to claim 1, further comprising a rake face (58) adjacent to the first cutting edge portion (24a).
15. A double-sided, indexable cutting insert (10) for a milling cutter (100) according to claim 14, further comprising a chip breaker (60) adjacent to the rake face (58).
16. A double-sided, indexable cutting insert (10) for a milling cutter (100) according to claim 1, wherein the first cutting edge portion (24a) is located higher than the central planar seating surface (17), and the second cutting edge portion (24b) is located lower than the central planar seating surface (17).
17. Shank (102) and, An upper part (104) having an insert pocket (110), wherein the insert pocket (110) includes a bottom seating surface (112), an axial seating surface (114), and a radial seating surface (116), The cutting insert (10) described in claim 1 is attached to the insert pocket (110), Milling cutter (100).
18. The milling cutter (100) according to claim 17, wherein the cutting insert (10) defines an angle (A) in the range of approximately 0 degrees to approximately 90 degrees, starting from the outer rake angle (118) and passing through the central axis (108) of the milling cutter (100).
19. The milling cutter (100) according to claim 17, wherein the recessed region (66, 70) of the cutting insert (10) defines a radius (R) in the range of approximately 0.5 mm to approximately 20 mm.
20. The milling cutter (100) according to claim 19, wherein the radius (R) defines a ramping angle (B) in the range of about 0 degrees to about 90 degrees.