Indexable milling insert and tool

Abstract

The present application relates to a kind of indexable milling inserts, comprising: insert body, the insert body has rake face, cutting edge, relief face and bottom surface, the bottom surface is oppositely arranged with the rake face, the two sides of the relief face are respectively connected with the rake face and the bottom surface, the rake face and the relief face intersection form the cutting edge;The rake face includes first rake face and second rake face connected with the first rake face, the second rake face is curved surface, and the corresponding rake angle γ of the second rake face increases from the position close to the cutting edge to the direction away from the cutting edge. Wherein the indexable milling insert is provided with second rake face, as the corresponding rake angle γ of the curved surface second rake face increases from the position close to the cutting edge to the direction away from the cutting edge, the adaptive rake angle design makes that the insert can reduce cutting resistance during milling process, and then improve the life of tool.

Description

Technical Field

[0001] This invention relates to the field of cutting tool technology, and in particular to an indexable milling tool. Background Technology

[0002] With the rapid development of machinery, the demand for high-precision products places increasingly stringent requirements on cutting tools. Structures with vertical sidewalls, cavities, or radial interference can only be machined using square shoulder milling cutters. However, solid milling cutters are expensive and consume a large amount of material, significantly increasing costs. Therefore, indexable square shoulder milling cutters, which are inexpensive and flexible in application, have become the best alternative. However, due to their unique cutter shape, indexable square shoulder milling cutters generate primarily radial cutting forces. These radial forces can easily lead to abnormal tool vibration, resulting in surface chatter marks and abnormal insert chipping. Consequently, the product machining quality and tool life fail to meet customer requirements.

[0003] Currently, manufacturers on the market mainly use carbide tool holders and anti-vibration tool holders to avoid abnormal vibrations in the aforementioned working conditions. However, the cost of these tools is too high for general cutting operations. Therefore, we need to optimize the insert structure and design an insert that meets the requirements of these working conditions. Summary of the Invention

[0004] Therefore, it is necessary to provide an indexable milling insert and tool to address the problem of insert chipping caused by abnormal tool vibration. The insert includes: an insert body having a rake face, a cutting edge, a flank face, and a bottom surface, wherein the bottom surface is disposed opposite to the rake face, and the two sides of the flank face are respectively connected to the rake face and the bottom surface, and the cutting edge is formed at the intersection of the rake face and the flank face; the rake face includes a first rake face and a second rake face connected to the first rake face, the second rake face is a curved surface, and the rake angle γ corresponding to the second rake face increases from the position close to the cutting edge to the direction away from the cutting edge.

[0005] In one embodiment, the rake face further includes a cutting edge width surface, the first rake face is disposed around the second rake face, and the two sides of the cutting edge width surface are respectively connected to the second rake face and the cutting edge.

[0006] In one embodiment, in the orthogonal plane, with the cutting edge as the origin, the x-axis is parallel to the base plane, and the y-axis is perpendicular to the x-axis. The curve formed by the rake face in the orthogonal plane satisfies the formula y = a*x. 2+b*x, where the front angle γ satisfies the formula γ=actan(2*a*x+b), and -90°<γ<90°; where y represents the coordinate of the curve on the y-axis, x represents the coordinate of the curve on the x-axis, a is a constant, and b is a constant.

[0007] In one embodiment, the values ​​of the constants a and b are in the range of -1.5 ≤ a < 0 and -1 ≤ b ≤ 2.

[0008] In one embodiment, the flank face includes a first flank face and a second flank face, the two sides of the first flank face are respectively connected to the cutting edge and the second flank face, and the first clearance angle α1 formed by the first flank face is smaller than the second clearance angle α2 formed by the second flank face.

[0009] In one embodiment, the width of the first back face is m, and the value of the width m is in the range of 0.01mm≤|m|≤0.25mm; and / or, the range of the first back angle α1 is 0°<α1≤5°, and the range of the second back angle α2 is 3°≤α2≤15°.

[0010] In one embodiment, the cutting edge includes a main cutting edge, a tip arc edge, a secondary cutting edge, and a finishing edge. The secondary cutting edge and the finishing edge are located on the same side of the milling insert and on a different side from the main cutting edge. The tip arc edge is located at the corner of the milling insert, and the two sides of the tip arc edge are respectively connected to the main cutting edge and the finishing edge.

[0011] In one embodiment, the flank face further includes a third flank face, a finishing flank face that intersects with the front face to form a finishing edge, and a secondary flank face that intersects with the front face to form the secondary cutting edge. The two sides of the third flank face are respectively connected to the second flank face and the bottom face.

[0012] In one embodiment, the projection of the milling insert on the bottom surface is a quadrilateral, the milling insert has two sets of oppositely arranged cutting edges, the tip arc edges of the two sets of cutting edges are respectively located at opposite corners of the milling insert, and the height of the main cutting edge, the secondary cutting edge and the finishing edge from the bottom surface increases from the end away from the tip arc edge to the end closer to the tip arc edge.

[0013] An indexable milling cutter includes a cutter body, wherein the milling insert is disposed on the cutter body.

[0014] This application provides an indexable milling insert and a cutting tool, wherein the indexable milling insert is provided with a second rake face, and the rake angle γ corresponding to the second rake face, which is a curved surface, increases from a position close to the cutting edge to a direction away from the cutting edge. This adaptive rake angle design allows the insert to reduce cutting resistance during milling, thereby improving tool life. Attached Figure Description

[0015] Figure 1 This is a three-dimensional structural schematic diagram of the indexable milling insert provided in the embodiments of this application;

[0016] Figure 2 This is a top view of the indexable milling insert provided in the embodiments of this application;

[0017] Figure 3 This is a schematic diagram of the indexable milling tool provided in the embodiments of this application;

[0018] Figure 4 yes Figure 3 A schematic cross-sectional view of the milling insert in an orthogonal plane;

[0019] Figure 5 yes Figure 4 A magnified view of a section at point F in the middle;

[0020] Icon labels:

[0021] 1-Milling insert;

[0022] 11-Front face;

[0023] 111 - First rake face;

[0024] 112 - Second rake face;

[0025] 113 - Blade width face;

[0026] 12- Screw hole;

[0027] 13-Cutting edge;

[0028] 131 - Main cutting edge;

[0029] 132 - Rounded blade tip;

[0030] 133-wiping blade;

[0031] 134 - Secondary cutting edge;

[0032] 14-Rear face;

[0033] 141 - First flank face;

[0034] 142 - Second flank face;

[0035] 143 - Third flank face;

[0036] 144 - Repair the blade surface after polishing;

[0037] 145 - Secondary back face;

[0038] 15-Bottom;

[0039] 2- Fastening screws;

[0040] 3-Blade body. Detailed Implementation

[0041] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0042] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0043] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0044] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0045] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0046] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0047] See Figure 1 , Figure 1 A partial perspective view of a milling insert according to an embodiment of the present invention is shown. An embodiment of the present invention provides an indexable milling insert and tool, comprising: an insert body having a rake face 11, a cutting edge 13, a flank face 14, and a bottom surface 15; the bottom surface 15 is disposed opposite to the rake face 11; the two sides of the flank face 14 are respectively connected to the rake face 11 and the bottom surface 15; the cutting edge 13 is formed at the intersection of the rake face 11 and the flank face 14; the rake face 11 includes a first rake face 111 and a second rake face 112 connected to the first rake face 111; the second rake face 112 is a curved surface, and the rake angle γ corresponding to the second rake face 112 increases from a position close to the cutting edge 13 towards a direction away from the cutting edge 13.

[0048] In this embodiment, the indexable milling insert 1 is provided with a second rake face 112. The rake angle γ corresponding to the second rake face 112, which is a curved surface, increases from the position close to the cutting edge 13 to the direction away from the cutting edge 13. This adaptive rake angle design allows the insert to reduce cutting resistance and abnormal vibration generated during milling, thereby improving tool life and improving the surface quality of the machined product.

[0049] In this embodiment, please refer to Figure 2The milling insert 1, viewed from above, is a parallelogram, consisting of a rake face 11, a cutting edge 13, a flank face 14, and a bottom face 15. Each part is rotationally symmetrical about the axis of rotation of the screw hole 12. It should be noted that the milling insert 1 is not strictly a parallelogram when viewed from above; its edges are formed by curves.

[0050] In this embodiment, the base plane (Pr) refers to a plane passing through a selected point on the cutting edge 13 and perpendicular to the main motion direction. Typically, it is parallel (or perpendicular) to the mounting surface (or axis) on the tool. For example, the base plane Pr of a typical lathe tool can be understood as parallel to the bottom surface 15 of the tool. The cutting plane (Ps) refers to a plane passing through a selected point on the cutting edge 13, tangent to the cutting edge 13, and perpendicular to the base plane Pr. It is also the plane formed by the cutting edge 13 and the cutting speed direction. In simpler terms, the cutting plane is the plane formed by the cutting edge 13 extending in a direction perpendicular to the base plane. That is, the "cutting surface" is the surface that needs to be machined with the tool, and the "base plane" is the reference surface of the workpiece being machined. The reference plane is the center; both the cutting surface and the orthogonal plane need a reference. The orthogonal plane (Po) refers to a plane passing through a selected point on the cutting edge 13 and perpendicular to both the base plane Pr and the cutting plane Ps. The base plane, the cutting plane, and the orthogonal plane are all perpendicular to each other. The datum plane is the center. Both the cutting surface and the orthogonal plane originate from the datum. Without the datum, it is impossible to accurately construct the cutting surface and the orthogonal plane.

[0051] In one embodiment, the rake face 11 further includes a cutting edge 113. The first rake face 111 is disposed around the second rake face 112, and the two sides of the cutting edge 113 are respectively connected to the second rake face 112 and the cutting edge 13. The cutting edge 113, which serves to cut and remove chips, also improves the strength of the cutting edge 13 and extends the service life of the milling insert 1.

[0052] In one embodiment, such as Figure 5 As shown, in the orthogonal plane Z under static installation conditions, with point P as the origin, the x-axis parallel to the base plane Pr, and the y-axis perpendicular to the x-axis, a two-dimensional xy coordinate system is established. Then, the curve q obtained by the intersection of the second rake face 112 and the orthogonal plane Z satisfies formula 1: y = a*x 2The angle between the tangent line at any point on curve q and the x-axis is the front angle γ. According to basic mathematical theory, the derivative of formula 1 yields the tangent function formula 2 for any point on curve q: y = 2ax + b. Taking the arctangent function of tangent function formula 2 yields the function formula 3 for the front angle γ: γ = actan(2ax + b), in degrees, with a range of -90 < γ < 90. The constant in the formula has a range of -1.5 ≤ a < 0 and -1 ≤ b ≤ 2. Compared to conventional planar rake faces, this design improves tool sharpness (i.e., reduces wedge angle β) while maintaining tool tip strength (i.e., keeping the rake angle γ constant). Furthermore, it can "adaptively" obtain a larger rake angle in machining with a larger feed per tooth (because the increased feed per tooth makes the absolute value of x in Formula 3 larger), thereby reducing cutting resistance and abnormal vibration. This, in turn, reduces chipping caused by abnormal vibration, improves tool life, and the rake angle γ changes in a stable linear manner, making cutting more stable.

[0053] In one embodiment, the flank face 14 includes a first flank face 141 and a second flank face 142. The two sides of the first flank face 141 are respectively connected to the cutting edge 13 and the second flank face 142, and the first clearance angle α1 formed by the first flank face 141 is smaller than the second clearance angle α2 formed by the second flank face 142. The width of the first flank face 141 is m, and the value of the width m is in the range of 0.01mm≤|m|≤0.25mm. The range of the first clearance angle α1 is 0°<α1≤5°, and the range of the second clearance angle α2 is 3°≤α2≤15°. In this embodiment, the intersection line of the first flank face 141 and the orthogonal plane Z is m, and its length ranges from 0.01mm ≤ |m| ≤ 0.25mm. The angle between the intersection line m and the y-axis is the first flank angle α1, and its ranges from 0° < α1 ≤ 5°. When the milling insert participates in cutting, the gap between the first flank face 141 and the machined surface is small. Due to the springback of the workpiece and the small |m|, the first flank face 141 is in close contact with the machined surface, avoiding abnormal vibration between the tool and the workpiece, thereby reducing chipping caused by abnormal vibration and improving tool life. Because its length is short, it will not cause abnormal increase in cutting resistance. We call it the "vibration-damping flank face 14". The vibration-damping flank face 14 mainly exists at the main cutting edge 131, the tool tip arc, and the finishing edge 133. The intersection line of the second flank face 142 and the orthogonal plane Z is n. The angle between the intersection line n and the y-axis is the second flank angle α2, which has a range of 3°≤α2≤15°. The length of the intersection line n is determined by the second flank angle α2. When the milling insert participates in cutting, there is a certain gap between the second flank face 142 and the machined surface due to the existence of the second flank angle α2. This prevents the machined surface from having excessive contact with the second flank face 142 when it springs back, thereby reducing friction and improving tool life.

[0054] In one embodiment, the cutting edge 13 includes a main cutting edge 131, a tip arc edge 132, a secondary cutting edge 134, and a finishing edge 133. The secondary cutting edge 134 and the finishing edge 133 are located on the same side of the milling insert and on a different side from the main cutting edge 131. The tip arc edge 132 is located at the corner of the milling insert, and the two sides of the tip arc edge 132 are respectively connected to the main cutting edge 131 and the finishing edge 133.

[0055] In this embodiment, a cutting edge 13 is provided at the intersection of the rake face 11 and the flank face 14. The cutting edge 13 has a main cutting edge 131, a tool tip arc edge 132, a finishing edge 133, and a secondary cutting edge 134. The main cutting edge 131 participates in radial cutting, the finishing edge 133 is used to finish the machined surface to improve the quality of the machined surface, and the tool tip arc edge 132 is designed with different sizes according to actual needs, which plays the role of strengthening the local strength at the corner of the workpiece.

[0056] In this embodiment, the cutting edge 13 is located at the intersection between the rake face 11 and the flank face 14, so that the cutting edge 13 can be in the optimal cutting position during the working milling process of the indexable milling tool, while also ensuring the stable fixation of the cutting edge 13.

[0057] In one embodiment, the flank face 14 further includes a third flank face 143, a finishing edge flank face 144 that intersects with the rake face 11 to form a finishing edge 133, and a secondary flank face 145 that intersects with the rake face 11 to form the secondary cutting edge 134. The two sides of the third flank face 143 are respectively connected to the second flank face 142 and the bottom surface 15.

[0058] In this embodiment, the flank face 14 further includes a third flank face 143, a finishing flank face 144, and a finishing flank face 144. The first flank face 141 is connected to the cutting edge surface 113, the second flank face 142 is connected to the first flank face 141, the third flank face 143 is disposed on the side of the milling insert 1, and the finishing flank face 144 is connected to the finishing edge 133. The finishing flank face 144 is disposed on the side of the milling insert. The flank face 14 has a first flank face 141, a second flank face 142, and a third flank face 143. The first flank face 141 contacts the machined surface of the workpiece and acts as a vibration damping agent. The second flank face 142 prevents the milling insert from interfering with the machined surface, resulting in poor surface quality. The third flank face 143 keeps the milling insert pressed tightly against the cutter body 3.

[0059] In one embodiment, the projection of the milling insert on the bottom surface 15 is quadrilateral. The milling insert has two sets of oppositely arranged cutting edges 13. The tip arc edges 132 of the two sets of cutting edges 13 are located at opposite corners of the milling insert. The height of the main cutting edge 131, the secondary cutting edge 134 and the finishing edge 133 from the bottom surface 15 increases from the end away from the tip arc edge 132 to the end closer to the tip arc edge 132.

[0060] In this embodiment, the milling insert is provided with two sets of opposing cutting edges 13, so that only one cutting edge 13 needs to be used in a single cutting operation. When one cutting edge 13 loses its functionality due to wear, it can be rotated 180° to use the other cutting edge 13, improving economy.

[0061] This application embodiment also provides an indexable milling cutter, including a cutter body 3, wherein the milling insert is disposed on the cutter body 3.

[0062] In this embodiment, the tool body 3 has a positioning surface, and the third flank face 143 and the finishing flank face 144 of the milling insert are fixedly connected to the positioning surface of the tool body 3. The connection method between the milling insert and the tool body 3 is not limited; it can be any connection method that can ensure a stable connection, such as: the milling insert 1 is mounted to the tool body 3 by a fastening screw 2, etc.

[0063] This application provides an indexable milling insert and tool. Compared with a conventional planar rake face 11, the first rake face 111 of this design, while ensuring the strength of the tool tip (i.e., the rake angle γ remains unchanged), can improve the tool sharpness (i.e., the wedge angle β becomes smaller). Furthermore, in cutting with a larger feed per tooth, it can "adaptively" obtain a larger rake angle (because the increased feed per tooth makes the absolute value of x in the formula γ = actan(2·a·x+b) larger), thereby reducing cutting resistance and abnormal vibration, thus reducing chipping caused by abnormal vibration, increasing tool life, and the rake angle γ is a stable linear value. The changes can make the cutting more stable. When the milling insert participates in the cutting, the gap between the first flank face 141 and the machined surface is small. Due to the springback of the workpiece and the small absolute value of the length of the second intersection line, the first flank face 141 is in close contact with the machined surface, avoiding abnormal vibration between the tool and the workpiece, thereby reducing chipping caused by abnormal vibration and improving tool life. The second flank face 142 has a certain gap with the machined surface due to the existence of the second clearance angle, which prevents the machined surface from contacting the second flank face 142 too much when it springs back, thereby reducing friction and improving tool life.

[0064] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0065] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. An indexable milling insert, characterized in that, The indexable milling insert includes: The insert body has a rake face, a cutting edge, a flank face, and a bottom surface. The bottom surface is disposed opposite to the rake face. The two sides of the flank face are respectively connected to the rake face and the bottom surface. The cutting edge is formed at the intersection of the rake face and the flank face. The rake face includes a first rake face and a second rake face connected to the first rake face. The second rake face is a curved surface, and the rake angle γ corresponding to the second rake face increases from the position close to the cutting edge to the direction away from the cutting edge. A plane perpendicular to the main motion direction is designated as the base plane through the point selected by the cutting edge, a plane tangent to the cutting edge and perpendicular to the base plane is designated as the cutting plane, and a plane perpendicular to both the base plane and the cutting plane is designated as the orthogonal plane. In the orthogonal plane, with the cutting edge as the origin, the x-axis is parallel to the base plane, and the y-axis is perpendicular to the x-axis. The curve formed by the rake face in the orthogonal plane satisfies the formula y=a*x. 2 +b*x, the front angle γ satisfies the formula γ=actan(2*a*x+b), and -90°<γ<90°, γ is a stable linear change; Wherein, y represents the coordinate of the curve on the y-axis, x represents the coordinate of the curve on the x-axis, a is a constant, b is a constant, and the values ​​of the constants a and b are in the range of -1.5≤a<0, -1≤b≤2.

2. The indexable milling insert according to claim 1, characterized in that, The rake face also includes a cutting edge width surface, the first rake face is arranged around the second rake face, and the two sides of the cutting edge width surface are respectively connected to the second rake face and the cutting edge.

3. The indexable milling insert according to claim 1, characterized in that, The flank face includes a first flank face and a second flank face. The two sides of the first flank face are respectively connected to the cutting edge and the second flank face, and the first flank angle α1 formed by the first flank face is smaller than the second flank angle α2 formed by the second flank face.

4. The indexable milling insert according to claim 3, characterized in that, The width of the first back face is m, and the value of the width m is in the range of 0.01mm≤|m|≤0.25mm; and / or, the range of the first back angle α1 is 0°<α1≤5°, and the range of the second back angle α2 is 3°≤α2≤15°.

5. The indexable milling insert according to claim 4, characterized in that, The cutting edge includes a main cutting edge, a tip arc edge, a secondary cutting edge, and a finishing edge. The secondary cutting edge and the finishing edge are located on the same side of the milling insert and on a different side from the main cutting edge. The tip arc edge is located at the corner of the milling insert, and its two sides are connected to the main cutting edge and the finishing edge, respectively.

6. The indexable milling insert according to claim 5, characterized in that, The flank face also includes a third flank face, a finishing flank face that intersects with the front face to form a finishing edge, and a secondary flank face that intersects with the front face to form the secondary cutting edge. The two sides of the third flank face are respectively connected to the second flank face and the bottom face.

7. The indexable milling insert according to claim 5, characterized in that, The projection of the milling insert on the bottom surface is a quadrilateral. The milling insert has two sets of oppositely arranged cutting edges. The tip arc edges of the two sets of cutting edges are located at opposite corners of the milling insert. The height of the main cutting edge, the secondary cutting edge, and the finishing edge from the bottom surface increases from the end away from the tip arc edge to the end closer to the tip arc edge.

8. An indexable milling tool, characterized in that, It includes a tool body and an indexable milling insert as described in any one of claims 1 to 7, the milling insert being mounted on the tool body.

Images