Round indexable milling blade

Abstract

According to the circular indexable milling blade, the blade body is in the shape of the big-end-up circular truncated cone, the periphery of the upper surface is circular, the periphery of the lower surface is polygonal, and the polygonal linear section of the periphery of the lower surface corresponds to the positioning face of the side face. In addition, the cutting edge is formed by intersecting the front tool face and the rear tool face of the blade, the cutting edge part is composed of the arc section and the linear section, the requirement for rough machining can be met, and semi-finish machining and finish machining can be completed.

Description

Technical Field

[0001] The invention belongs to the field of cutting tools, and in particular relates to a circular indexable milling insert. Background Art

[0002] During milling, blades often need to be replaced due to chipping or wear, which not only affects processing efficiency, but also greatly wastes production time. In order to improve the speed and efficiency of blade replacement and maximize the utilization of single blades, indexable blades came into being. This type of blade not only significantly improves the utilization rate of single blades, thereby enhancing economic efficiency, but also can be replaced in a short time, greatly shortening the processing cycle and improving the overall operating efficiency of the machine tool.

[0003] The invention application with publication number CN108907254A discloses a tool body, including a tool body, the tool body is in a truncated cone shape, the edge of the large end face of the tool body is the main cutting edge, the large end face of the tool body is the front cutting edge, the outer peripheral surface of the tool body is the back cutting edge, the angle between the back cutting edge and the axis of the tool body is the back angle, the back angle is 0°-30°, a positioning hole is provided in the middle of the tool body, and a clearance is provided on the back cutting edge. This application enables the truncated cone tool body to fully utilize the cutting edge, greatly increase the metal removal rate, save processing time, be wear-resistant and not easy to collapse, and can be rotated a certain angle for reuse after being worn out, and one tool body can be used repeatedly many times.

[0004] Although the above technical solution effectively improves the utilization rate of the tool cutting edge through the indexing function, thereby significantly extending the service life of a single blade, there are still some shortcomings in actual use. When the blade is worn and needs to be indexed, the blade still needs to be completely disassembled, which means that the tool change speed has not been substantially improved, and the tool change time has not been significantly reduced. Although the efficiency of the blade has been greatly improved, the convenience of tool change still needs to be optimized. In addition, during the installation process, although the back blade is designed with an air avoidance structure, since its upper and lower surfaces are directly connected, precise alignment is still required during installation, otherwise it is difficult to fix and adjust the screws. What is more noteworthy is that the front blade face of the blade is flat, which is not very suitable in the field of modern processing, especially in semi-finishing and finishing. With the continuous advancement of substrate materials, coating processes and chip breaking groove types, the application range of circular milling inserts has become increasingly wide, and the design requirements for the front blade face have become increasingly high. Summary of the invention

[0005] Based on this, the present invention aims to overcome the defects of the prior art and provide a milling insert that can be indexed without complete disassembly.

[0006] A circular indexable milling insert, which is generally in the shape of a truncated cone with a larger top and a smaller bottom, comprising:

[0007] The upper surface is circular as a whole and includes a rake face, which has a circular circumference as its outer circumference and extends a certain width toward the center of the circle in the radial direction to form a circular or approximately circular rake face. The rake face is inclined toward the center of the blade, and the section at any point on the circular curved surface forms an angle of 5°-20° with the reference plane.

[0008] The lower surface is arranged opposite to the upper surface, and the outer circumference is a regular polygon as a whole. The middle section of the side of the polygon is a straight line, and the adjacent straight lines are connected by arc transition. The area of ​​the lower surface is smaller than that of the upper surface.

[0009] Preferably, the outer periphery of the lower surface is a regular hexagon as a whole.

[0010] The fastening hole passes through the upper and lower surfaces and is used to install a fastening screw or other fasteners for fixing the blade to the blade body.

[0011] The back cutting edge is formed by extending the upper surface toward the lower surface. Since the area of ​​the upper surface is larger than that of the lower surface, the back cutting edge is in the shape of an inverted cone as a whole. The angle between the section at any point on the back cutting edge and the center axis of the blade is in the range of 10°-20°.

[0012] The lower surface extends toward the upper surface to form a positioning surface and a transition surface. The middle section of the lower surface outer circumference extends toward the upper surface to form the positioning surface. The arc section of the lower surface outer circumference extends toward the upper surface to form the transition surface. The transition surface and the positioning surface are arranged one by one.

[0013] The angle between the positioning surface and the central axis ranges from 8° to 15°, and the angle between the transition surface and the central axis ranges from 10° to 11.5°.

[0014] The upper surface and the back cutting surface extending therefrom, i.e., the upper half of the blade, are conical in shape, and the lower surface and the positioning surface and transition surface extending therefrom, i.e., the lower half of the blade, are hexagonal in shape. The upper half of the blade and the lower half of the blade are transitionally connected by a connecting surface, and the connecting surface can be a curved surface or a plurality of planes having angles with each other, and the angle between the connecting surface and the back cutting surface ranges from 10° to 45°, and the angle between the connecting surface and the central axis is greater than the angle between the back cutting surface and the central axis.

[0015] Wherein, a reasonable angle between the flank surface and the positioning surface is set within the above-mentioned angle range so that the extension surface of the flank surface in the downward surface direction does not intersect with the positioning surface.

[0016] During the installation and use of the blade, the positioning surface contacts the raised part of the blade fixing groove of the cutting tool in a line contact manner, which plays the role of positioning and fixing the blade. It not only facilitates the positioning of the blade during installation, but also prevents the blade from rotating and offsetting during use, affecting the processing effect.

[0017] The rake face and the flank face intersect to form a cutting edge. From the vertical cross section through the center axis, the cutting edge portion is composed of an upwardly arched arc segment and a straight line segment. One side of the arc segment is connected to the rake face, and the other side of the arc segment is connected to the straight line segment. The straight line segment is inclined downward and the angle between the straight line segment and the reference plane is 16°-19°. The other side of the straight line segment is connected to the flank face, and the angle between the rake face and the flank face is 33°-37°.

[0018] The advantages of this application compared to the prior art are:

[0019] 1. The present invention is in the shape of a truncated cone with a larger upper part and a smaller lower part. The outer periphery of the lower surface of the blade is a regular polygon, which corresponds to the positioning surface on the side of the lower half of the blade. When in use, the positioning surface contacts the raised part of the blade fixing groove to fix the blade. When the cutting edge of the blade is chipped, the cutting edge can be replaced by switching a positioning surface, and the processing can be continued, which saves the time of repeatedly replacing the blade, and at the same time improves the utilization efficiency of a single blade, effectively reducing the processing cost.

[0020] 2. The fastening hole in the present invention passes through the upper and lower surfaces, the area of ​​the lower surface is smaller than that of the upper surface, and through reasonable angle setting, the extension surface of the rear blade facing the lower surface does not intersect with the positioning surface, and the angle between the connecting surface and the central axis is large. The blade can be rotated to achieve indexing without completely removing the fastener, and there is no need to repeatedly disassemble the blade, saving time and cost.

[0021] 3. In an optional embodiment, the front cutting edge and the rear cutting edge of the present invention are connected by an upwardly arched arc segment and a straight line segment, which together constitute the cutting edge portion, wherein there is an angle of 17.5° between the straight line segment and the reference plane, so that the cutting blade of the present invention can not only complete rough machining, but also semi-finishing and finishing, expanding the application scenarios of circular indexable milling blades, which are sufficient to meet various precision machining requirements.

[0022] 4. The outer periphery of the lower surface is a regular polygon, and the side surfaces corresponding to the middle sections of the multiple faces of the polygon are positioning surfaces, which can ensure the stability of the blade during the milling process and prevent the blade from rotating around the central axis during use.

[0023] 5. The contact part between the blade positioning surface and the blade body fixing groove of the present invention is line contact, which can effectively prevent the blade from rotating around the central axis during use. Since the contact part between the blade positioning surface and the blade body fixing groove is an inclined surface, when the surface contacts, if there is an angle deviation of one surface, then the surface contact cannot be achieved. At the same time, the roughness of the processed surface can easily turn the surface contact into point contact, so line contact is more stable than surface contact. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a three-dimensional schematic diagram of a circular indexable milling insert.

[0025] Figure 2 A bottom view of a circular indexable milling insert.

[0026] Figure 3 A side view of a circular indexable milling insert along the LL direction.

[0027] Figure 4 This is a cross-sectional view of a circular indexable milling insert along the LL line.

[0028] Figure 5 This is a bottom view of a circular indexable milling insert from another angle (where the MM line is perpendicular to the LL line, i.e. Figure 5 and Figure 2 There is a 90° angle difference between them).

[0029] Figure 6 It is a side view of a circular indexable milling insert along the MM direction.

[0030] Figure 7 This is a cross-sectional view of a circular indexable milling insert along the MM line.

[0031] Figure 8 It is a side view of a circular indexable milling insert from another direction.

[0032] Fig. 9 for Figure 8 A partial enlarged view of the F area.

[0033] Reference numerals:

[0034] 1. Upper surface; 101. Rake face; 2. Lower surface; 3. Fastening hole; 4. Flank face; 5. Positioning face; 6. Transition face; 7. Connecting face; 8. Cutting edge; α. Center axis; LL. Straight line passing through two relative positioning faces; MM. Straight line passing through two relative transition faces; 801. Cutting edge arc segment; 802. Cutting edge straight line segment.

[0035] The LL line and the MM line are perpendicular to each other and are both symmetry axes of the lower surface. DETAILED DESCRIPTION

[0036] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0037] The present application embodiment provides a circular indexable milling insert, such as Figure 1 As shown, the indexable milling insert is approximately in the shape of a truncated cone, or in the shape of a combination of two truncated cones, one large and one small, or in the shape of a combination of a larger truncated cone and a smaller polygonal cone structure, and includes: a cutting edge 8, an upper surface 1, a lower surface 2, a back tool surface 4, a positioning surface 5, a connecting surface and a fastening hole 3.

[0038] The cutting edge is arranged on one end face of the indexable milling blade and is circular or annular. A virtual reference plane or a group of virtual, mutually parallel reference planes are defined by the circular or annular cutting edge.

[0039] The upper surface 1 is approximately circular or annular, and includes a rake face 101 . The outer edge of the rake face 101 is connected to the cutting edge and extends in a radial direction toward the center of the circle by a certain width. The overall shape is approximately annular.

[0040] Optionally, the rake face 101 forms an angle of 5°-20° with the reference plane.

[0041] The lower surface 2 is arranged opposite to the upper surface 1 and is approximately a regular polygon as a whole, preferably a regular hexagon.

[0042] The indexable milling insert has a central axis α that passes through the upper surface 1 and the lower surface 2 and is rotationally symmetrical about the central axis α of the insert.

[0043] Optionally, the diagonals of the lower surface 2 are chamfered, that is, the edges of the lower surface 2 are transitioned by arcs, and the area of ​​the lower surface 2 is smaller than that of the upper surface 1 .

[0044] The flank surface 4 is formed by extending between the upper surface 1 and the lower surface 2, and the flank surface 4 is connected to the rake surface 101 through the cutting edge. Since the area of ​​the upper surface 1 is larger than that of the lower surface 2, the flank surface 4 is approximately the side surface of an inverted cone, and gradually shrinks from one end close to the upper surface 1 to one end close to the lower surface 2.

[0045] Optionally, the angle between the flank surface 4 and the central axis α of the insert is in the range of 10°-20°, or in other words, the angle between the tangent plane at any point of the flank surface 4 and the central axis α of the insert is in the range of 10°-20°.

[0046] The fastening hole 3 passes through the upper surface 1 and the lower surface 2 and is used for installing a fastening screw or other fasteners having a fixing function, which is a fastening screw in this embodiment, to fix the blade to the blade body.

[0047] like Figure 2-Figure 7As shown, the lower surface 2 extends toward the upper surface 1 to form a positioning surface 5 and a transition surface 6. The straight edge of the lower surface 2 extends toward the upper surface 1 to form the positioning surface 5. The arc segment of the lower surface 2 extends toward the upper surface 1 to form the transition surface 6. The transition surface 6 and the positioning surface 5 are arranged one by one.

[0048] like Figure 4 As shown, the angle β between the positioning surface 5 and the central axis α is in the range of 8°-15°.

[0049] Preferably, Figure 7 As shown, the angle between the transition surface 6 and the central axis γ is in the range of 25°.

[0050] Optionally, the upper surface 1 and the flank surface 4 extending therefrom, i.e., the upper half of the blade, are conical; the lower surface 2 and the positioning surface 5 and transition surface 6 extending therefrom, i.e., the lower half of the blade, are hexagonal. The upper half of the blade and the lower half of the blade are transitionally connected by a connecting surface 7, and the connecting surface 7 can be a curved surface or a plurality of planes having angles with each other, and the angle between the connecting surface 7 and the flank surface 4 ranges from 10° to 45°, and the angle between the connecting surface 7 and the central axis α is greater than the angle between the flank surface 4 and the central axis α.

[0051] Among them, Figure 7 As shown, a reasonable angle between the back cutting surface 4 and the positioning surface 5 is set within the above-mentioned angle range so that the extension surface of the back cutting surface 4 toward the lower surface 2 does not intersect with the positioning surface 5. The blade can be rotated to replace the cutting edge by only loosening the fastening screws without completely disassembling the blade, which can effectively save the time cost of replacing the cutting edge.

[0052] During the installation and use of the blade, the positioning surface 5 contacts the raised part of the blade fixing groove of the cutting tool in a line contact manner, which plays the role of positioning and fixing the blade. It not only facilitates the positioning of the blade during installation, but also prevents the blade from rotating and offsetting during use, affecting the processing effect.

[0053] like Figure 1 As shown, the front cutting surface 101 intersects with the rear cutting surface 4 to form a cutting edge 8. Fig. 9 As shown, from the vertical cross section through the central axis, the cutting edge portion is composed of an upwardly arched arc segment 801 and a straight line segment 802. One side of the arc segment 801 is connected to the front cutting edge 101, and the other side of the arc segment 801 is connected to the straight line segment 802. The straight line segment 802 is inclined downward and the angle ω between it and the reference plane is 17.5°. The other side of the straight line segment 802 is connected to the back cutting edge 4, and the angle between the front cutting edge 101 and the back cutting edge 4 is 35°.

[0054] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A circular indexable milling insert, characterized in that: include: The upper surface has a circular outer circumference, and the outer circumference of the upper surface extends inwardly to a certain width to form a circular or approximately circular rake face, and the rake face is inclined toward the center of the blade; The lower surface is arranged opposite to the upper surface, and its outer periphery is generally a regular polygon, and the middle sections of the sides of the outer periphery are all straight line segments; The area of ​​the lower surface is smaller than that of the upper surface, and the blade is generally in the shape of a truncated cone with a larger top and a smaller bottom. A flank face, wherein the upper surface extends toward the lower surface to form a flank face; A positioning surface, wherein the straight line segment portion of the outer periphery of the lower surface extends toward the upper surface to form a positioning surface; Wherein, the extension surface of the rear cutting surface in the direction of the downward surface does not intersect with the positioning surface.

2. A circular indexable milling insert according to claim 1, characterized in that: The outer periphery of the lower surface is in a regular hexagon as a whole.

3. A circular indexable milling insert according to claim 1, characterized in that: The front cutting surface and the back cutting surface intersect to form a cutting edge. The cutting edge is composed of an upwardly arched arc segment and a straight line segment in cross section. One end of the arc segment is connected to the front cutting surface, and the other end is connected to the straight line segment. The other end of the straight line segment is connected to the back cutting surface.

4. A circular indexable milling insert according to claim 3, characterized in that: The angle between the straight line segment and the reference plane is 16°-19°.

5. A circular indexable milling insert according to claim 1, characterized in that: The included angle between the front cutting edge and the rear cutting edge is 33°-37°.

6. A circular indexable milling insert according to claim 1, characterized in that: The lower surface is in the shape of a regular hexagon, the middle section of the side of which is a straight line section, and the straight line sections are transitionally connected by arc sections.

7. A circular indexable milling insert according to claim 6, characterized in that: The arc segment of the outer circumference of the lower surface extends toward the upper surface to form a transition surface, and the positioning surface and the transition surface are arranged one by one with an interval.

8. A circular indexable milling insert according to claim 1, characterized in that: The front cutting edge forms an angle of 5°-20° with the reference plane.

9. A circular indexable milling insert according to claim 7, characterized in that: The positioning surface, the transition surface and the back cutting surface are transitioned by a connecting surface.

10. A circular indexable milling insert according to claim 9, characterized in that: The connecting surface is a curved surface.

11. A circular indexable milling insert according to claim 9, characterized in that: The connecting surface is composed of a plurality of planes which have angles with each other.

12. A circular indexable milling insert according to any one of claims 10 to 11, characterized in that: The included angle between the connecting surface and the back cutting surface is in the range of 10°-45°.

13. A circular indexable milling insert according to any one of claims 1 to 11, characterized in that: The angle between the positioning surface and the central axis of the blade is in the range of 8°-15°.

14. A circular indexable milling insert according to claim 7, characterized in that: The angle between the transition surface and the central axis of the blade is in the range of 10°-11.5°.

Images