Polygonal indexable cutting blade

Abstract

The utility model discloses a polygonal indexable cutting blade which comprises an upper surface and a lower surface which are arranged oppositely and are both polygonal. The rake faces are connected with the upper surface and are arranged in the circumferential direction of the upper surface; the peripheral side faces extend between the front cutter face and the lower surface and are distributed in the circumferential direction; and any group of cutting edges is formed at the intersection of any peripheral side surface and the rake face, and comprises a first main edge which is in a convex arc shape and a second main edge which is in a linear shape. The utility model aims to provide the polygonal indexable cutting blade which is not easy to tipping and stable in cutting.

Description

Technical Field

[0001] The utility model belongs to the technical field of machining tools, in particular to a polygonal indexable cutting blade. Background Art

[0002] In metalworking, high-feed cutting methods are often used for their efficiency, especially when conditions permit. Machining 90-degree shoulders is a common task, and for this reason, tool designs often combine primary cutting and finishing functions to meet roughness requirements while reducing machining time. To improve economic efficiency, multi-edge designs have emerged. Traditionally, a rectangular or triangular basic shape has evolved into an insert configuration with two or three parallel primary cutting edges. This design effectively staggers the primary and wiper cutting edges, preventing interference and potential damage.

[0003] Further optimization can be achieved by increasing the number of cutting edges and adjusting the clearance between the main cutting edge and the wiper edge to ensure the integrity of the main cutting edge. Furthermore, improvements to the main cutting edge can help reduce cutting resistance, lower the risk of chipping, and control chip flow, thereby avoiding scratches on the machined surface.

[0004] Patent document EP0956921A2 introduces an innovative tool that can process both 90-degree shoulders and bevels, and can operate flexibly in both axial and radial directions. The blade is a parallelogram, with the long side serving as the main cutting edge and the short side serving as a wiper edge, forming a right angle with the main cutting edge to smooth the machined surface and improve the finish. The junction between the main cutting edge and the bevel is smoothly rounded, and the curvature design enables a curved portion with a radius of 0.4-6.4mm to be obtained during the machining process. However, the patent only includes two main cutting edges, which limits their utilization efficiency.

[0005] Another patent document, US5597271A, describes a square, table-shaped, replaceable cutting insert. Its smaller end surface serves as the base, contacting and securing the cutter body. The larger end surface is provided with a rake face, which, together with the side surfaces, forms the cutting edge. The cutting edge consists of a continuous primary cutting edge and a secondary cutting edge (wiper edge). Each secondary cutting edge is spaced outward from its flank surface and offset toward the base, ensuring that it does not extend beyond its corresponding primary cutting edge when viewed from above. When installed in a cylindrical milling cutter, the primary cutting edge is specifically positioned to exhibit a positive axial rake angle and a negative radial angle. This maintains the spacing between the primary cutting edge and its adjacent secondary cutting edge during shoulder machining, while also ensuring that the secondary cutting edge maintains a distance from the machined shoulder surface, preventing wear and ensuring surface straightness. Although this design effectively staggers the primary and secondary cutting edges, preventing interference with the machined surface, wear on the side positioning surfaces during machining still exists, affecting installation accuracy after indexing. Furthermore, the linear primary cutting edge concentrates cutting resistance when entering the workpiece, which can easily lead to chipping. Utility Model Content

[0006] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a polygonal indexable cutting insert that is not prone to chipping and has smooth cutting performance.

[0007] The present application provides a polygonal indexable cutting insert, comprising:

[0008] An upper surface and a lower surface are oppositely arranged and both are polygonal;

[0009] a plurality of rake surfaces connected to the upper surface and arranged circumferentially around the upper surface;

[0010] a plurality of circumferential side surfaces extending between the rake face and the lower surface and arranged circumferentially;

[0011] Multiple groups of cutting edges, any group of cutting edges is formed at the intersection of any peripheral side surface and the rake face, including a first main edge in the shape of an upward convex arc and a second main edge in the shape of a straight line.

[0012] Furthermore, any group of the cutting edges includes a main edge, a wiper edge and a corner edge in sequence, the main edge includes the first main edge and the second main edge, and any of the peripheral side surfaces includes a flank surface.

[0013] Specifically, the height of the wiper edge is lower than that of the main edge, and the wiper edge and the wiper edge flank are respectively convex outward relative to the main edge and the main edge flank.

[0014] Furthermore, any of the rake surfaces includes an outer rake surface and an inner rake surface extending along the main edge direction, the outer rake surface is a curved surface, and the inner rake surface is an inclined surface inclined toward the upper surface.

[0015] Further, the outer rake surface includes a first outer rake surface extending along the first main edge and a second outer rake surface extending along the second main edge, and a rake angle of the first outer rake surface is different from a rake angle of the second outer rake surface.

[0016] Furthermore, any of the rake faces further comprises a wiper edge rake face extending along the wiper edge, and in a group of the cutting edges, the wiper edge rake face gradually increases from the corner edge to the main edge.

[0017] Specifically, the height of the first main edge is lower at one end away from the second main edge, and higher at one end close to the second main edge.

[0018] Specifically, the second main edge is parallel to the lower surface.

[0019] Specifically, the projection length of the first main edge on the plane where the lower surface is located is smaller than the projection length of the second main edge.

[0020] Specifically, the upper surface and the lower surface are corresponding parallelograms.

[0021] The improvements of this application provide the following advantages: The embodiments of this application improve the cutting edge, utilizing the convex arc-shaped first main edge to disperse the cutting force. This helps disperse the cutting force when cutting into the workpiece, thereby reducing cutting resistance and thus reducing edge chipping. The second main edge is straight, and after the first main edge cuts into the workpiece, the cutting force is stabilized. The subsequent straight shape can even out the cutting force, making the cutting more stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the three-dimensional structure of a polygonal indexable cutting insert according to an embodiment of the present application;

[0023] Figure 2 This is a schematic side view of the structure of a polygonal indexable cutting insert according to an embodiment of the present application;

[0024] Figure 3 for Figure 2 A partial enlarged view of the dotted box in the middle;

[0025] Figure 4 This is another schematic diagram of the three-dimensional structure of a polygonal indexable cutting insert according to an embodiment of the present application;

[0026] Figure 5 for Figure 4 A partial enlarged view of the dotted box in the middle;

[0027] Figure 6 This is another side structural diagram of a polygonal indexable cutting insert according to an embodiment of the present application;

[0028] Figure 7 for Figure 6 A partial enlarged view of the dotted box in the middle;

[0029] Among them: 1. Upper surface; 2. Lower surface; 3. Rake face; 31. External rake face; 311. First external rake face; 312. Second external rake face; 32. Internal rake face; 33. Wiper edge rake face; 4. Circumferential side surface; 41. Flank face; 42. Positioning surface; 43. Main edge flank face; 44. Wiper edge flank face; 5, 5', Cutting edge; 51, 51', Main edge; 52, Wiper edge; 53, Corner edge; 54, First main edge; 55, Second main edge; 6. Screw hole. DETAILED DESCRIPTION

[0030] The following describes the embodiments of the present invention through specific examples. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the details in this specification may be modified or altered based on different perspectives and applications without departing from the spirit of the present invention.

[0031] See also Figure 1-7 The embodiment of the present application provides a polygonal indexable cutting insert, comprising an upper surface 1 and a lower surface 2 arranged opposite to each other, a plurality of rake faces 3, a plurality of peripheral side faces 4, a plurality of cutting edges 5, 5' and a screw hole 6.

[0032] The upper surface 1 and the lower surface 2 are polygons of the same or similar shape and corresponding to each other. The lower surface 2 is a flat surface. The corners of the upper surface 1 and / or the lower surface 2 may be rounded.

[0033] The screw hole 6 is arranged at the geometric center of the cutting insert and passes through the middle of the upper surface 1 and the lower surface 2.

[0034] Multiple circumferential side surfaces 4 extend between the rake face 3 and the lower surface 2 and are arranged circumferentially. Each circumferential side surface 4 includes a flank face 41 and a positioning face 42, arranged one above the other. The flank face 41 abuts the cutting edge 5, and the positioning face 42 abuts the lower surface 2. The flank face 41 includes a main edge flank face 43 extending along the main edges 51, 51' and a wiper edge flank face 44 extending along the wiper edge 52.

[0035] A set of cutting edges 5 is formed at the intersection of any peripheral side surface 4 and the rake face 3 and comprises, in order, a main edge 51, a wiper edge 52, and a corner edge 53. The main edge 51 comprises a first main edge 54 in the shape of an upwardly convex arc and a second main edge 55 in the shape of a straight line. The corner edge 53 is located at the corner of the upper surface 1, i.e., at the intersection of the two sets of cutting edges 5, 5', connecting the main edges 51' and wiper edges 52 of the two adjacent sets of cutting edges 5, 5'.

[0036] Multiple rake faces 3 are connected to the upper surface 1 and are arranged circumferentially around the upper surface 1. Each rake face 3 includes an outer rake face 31 and an inner rake face 32 extending along the main edges 51, 51', and a wiper edge rake face 33 extending along the wiper edge 52. The outer rake face 31 is disposed between the main edge 51 and the inner rake face 32, connecting to the main edge 51 and the inner rake face 32, respectively. The inner rake face 32 is disposed between the first rake face 3 and the upper surface 1, connecting to the outer rake face 31 and the upper surface 1, respectively.

[0037] Specifically, any peripheral side surface 4 is formed by extending one side of the polygonal upper surface 1 to a corresponding side of the polygonal lower surface 2, such as Figure 1 As shown, the plurality of peripheral side surfaces 4 are contracted downward as a whole.

[0038] Specifically, any rake surface 3 is correspondingly formed on one side of the upper surface 1 .

[0039] Specifically, the outer rake face 31 is a curved surface, and the inner rake face 32 is an inclined surface inclined toward the upper surface 1. The insert is designed with a double rake angle, so it has a larger chip holding portion to accommodate chip accumulation and prevent chips from interfering with cutting.

[0040] like Figure 6 As shown, specifically, the upper surface 1 and the lower surface 2 are corresponding parallelograms.

[0041] like Figure 2 、 7 As shown, as an embodiment, the wiper edge 52 is lower than the main edges 51, 51' relative to the lower surface 2. With the center portion of the upper surface 1 as the inner portion, the wiper edge 52 and the wiper edge relief 44 protrude outward relative to the main edges 51, 51', and the main edge relief 43, respectively. In other words, when viewed from the normal to the upper surface 1, the wiper edge 52 and the wiper edge relief 44 protrude outward relative to the main edges 51, 51', and the main edge relief 43, respectively. The wiper edge relief 44 protrudes laterally to prevent side wear during machining, which could affect positioning. The main edge relief 43 is staggered from the wiper edge relief 44, with the latter protruding outward to prevent the unprocessed main edges 51, 51' from affecting the surface processed by the wiper edge 52.

[0042] like Figure 7As shown, as an embodiment, the outer rake face 31 includes a first outer rake face 311 extending along the first main edge 54 and a second outer rake face 312 extending along the second main edge 55. Since the first main edge 54 is in the shape of an upward convex arc and the second main edge 55 is in the shape of a straight line, the first outer rake face 311 is a curved surface in the shape of an upward convex arc and the second outer rake face 312 is a plane. Therefore, relative to the same base surface, the rake angle of the first outer rake face 311 gradually changes, while the rake angle of the second outer rake face 312 remains basically unchanged. By utilizing the rake angle change from the first outer rake face 311 to the second outer rake face 312, chip formation and control are improved, allowing the chips to flow out more smoothly.

[0043] like Figure 7 As shown, as an embodiment, within a set of cutting edges 5, 5', the wiper edge rake surface 33 gradually widens from the corner edge 53 to the main edge 51. The gradually widening width or area of the wiper edge rake surface 33 means that it gradually widens or increases from adjacent corner edges 53 to adjacent main edges 51. This effectively guides chips from the corner edge toward the main edge 51, preventing them from damaging the machined surface. Preferably, the cutting edge of the wiper edge 52 does not have a chamfer, which facilitates repairing the workpiece surface and improving its finish.

[0044] like Figure 3 As shown, as an embodiment, the first main edge 54 is curved, with its height relative to the lower surface 2 being lower at the end away from the second main edge 55 and higher at the end closer to the second main edge 55. Preferably, the second main edge 55 is linear and parallel to the lower surface 2. Preferably, the projection length of the first main edge 54 onto the plane of the lower surface 2 is shorter than the projection length of the second main edge 55.

[0045] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A polygonal indexable cutting insert, characterized in that: include: An upper surface and a lower surface are oppositely arranged and both are polygonal; a plurality of rake surfaces connected to the upper surface and arranged circumferentially around the upper surface; a plurality of circumferential side surfaces extending between the rake face and the lower surface and arranged circumferentially; Multiple groups of cutting edges, any group of cutting edges is formed at the intersection of any peripheral side surface and the rake face, including a first main edge in the shape of an upward convex arc and a second main edge in the shape of a straight line.

2. The polygonal indexable cutting insert according to claim 1, characterized in that: Any group of the cutting edges includes a main edge, a wiper edge and a corner edge in sequence, the main edge includes the first main edge and the second main edge, and any of the peripheral side surfaces includes a flank surface.

3. The polygonal indexable cutting insert according to claim 2, characterized in that: The height of the wiper edge is lower than that of the main edge, and the wiper edge and the wiper edge flank are respectively convex outward relative to the main edge and the main edge flank.

4. The polygonal indexable cutting insert according to claim 2, characterized in that: Any of the rake surfaces includes an outer rake surface and an inner rake surface extending along the main edge direction, the outer rake surface is a curved surface, and the inner rake surface is an inclined surface inclined toward the upper surface.

5. The polygonal indexable cutting insert according to claim 4, characterized in that: The outer rake surface includes a first outer rake surface extending along the first main edge and a second outer rake surface extending along the second main edge; accordingly, the first outer rake surface is an upward convex arc-shaped curved surface, and the second outer rake surface is a plane.

6. The polygonal indexable cutting insert according to claim 4, characterized in that: Any of the rake surfaces further includes a wiper edge rake surface extending along the wiper edge. In a group of the cutting edges, the wiper edge rake surface gradually increases from the corner edge to the main edge.

7. The polygonal indexable cutting insert according to any one of claims 1 to 6, characterized in that: The height of the first main edge is lower at an end away from the second main edge, and is higher at an end close to the second main edge.

8. The polygonal indexable cutting insert according to claim 7, characterized in that: The second main edge is parallel to the lower surface.

9. The polygonal indexable cutting insert according to any one of claims 1 to 6, characterized in that: The projection length of the first main edge on the plane where the lower surface is located is smaller than the projection length of the second main edge.

10. The polygonal indexable cutting insert according to any one of claims 1 to 6, characterized in that: The upper surface and the lower surface are corresponding parallelograms.

Images