Indexable milling insert and milling tool thereof

Abstract

The present invention relates to the technical field of tool design, and discloses an indexable milling blade, including a first cutting portion and a second cutting portion distributed in the length direction of the milling blade and having the same outer contour; the first cutting portion includes two main positioning surfaces distributed perpendicular to the thickness direction of the milling blade; the junction of the first cutting portion and the second cutting portion is a dislocation structure with an offset in the direction perpendicular to the main positioning surface, and the dislocation structure includes a first axial positioning surface located on the first cutting portion and a second axial positioning surface located on the second cutting portion; the second cutting portion rotates 180° around the center of the dislocation structure, and the projection coincides with the first cutting portion; the first cutting portion includes two centrally symmetrical cutting units, which include main cutting edges arranged parallel to the length direction of the milling blade. The milling blade has four main cutting edges in total, and only two main cutting edges with unequal tooth pitches on the circumference participate in cutting during cutting, which can be suitable for milling tools with small cutting diameters and can reduce cutting vibration.

Description

Technical Field

[0001] The invention relates to the technical field of tool design, and in particular to an indexable milling insert and a milling tool thereof. Background Art

[0002] The minimum diameter of ordinary indexable milling cutters is generally determined by the size of the milling inserts, and ordinary milling inserts cannot be made too small due to the screw hole structure and tool groove production. Therefore, it is difficult to design and manufacture ordinary indexable cutters into smaller diameter specifications on small-diameter milling cutters, so that when processing small cavities, more expensive solid carbide milling cutters have to be used. This limits the application of indexable milling cutters in the field of small-diameter milling cutters to a certain extent, thereby increasing the production cost of milling small cavity parts.

[0003] In addition, during the cutting process, the milling tool will inevitably produce cutting vibration. The milling vibration frequency of the equal pitch milling tool is high and is not suitable for milling parts with high surface quality requirements.

[0004] The patent with announcement number CN203437718U discloses a vibration-resistant high-speed indexable milling cutter, which includes: a cutter head, a blade, a first shank and a second shank; the cutter head is connected to the first end of the first shank, the cutter head has a plurality of mounting parts, the blade is mounted on the mounting parts, the first end of the second shank is welded to the second end of the first shank, and the welding surface is V-shaped; the cutter head, the first shank and the second shank are made of different materials. Through the above method, the vibration-resistant high-speed indexable milling cutter can effectively reduce the vibration amplitude generated by the shank during processing, thereby improving the surface finish and roundness of the processed hole, reducing the wear of the blade, reducing the possibility of producing a tapered hole, and further improving the cutting efficiency.

[0005] Although the above-mentioned indexable milling cutter can play a certain anti-vibration effect, this type of milling cutter is mainly used for deep hole processing and may not play the same technical effect when processing cavities. Therefore, it is necessary to develop a milling insert that is suitable for small cavity processing and has low vibration. Summary of the invention

[0006] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide an indexable milling insert that can be applied to smaller cutting diameters and can significantly reduce milling vibrations.

[0007] The present invention also provides a milling tool using the indexable milling insert.

[0008] The purpose of the present invention is achieved through the following technical solutions:

[0009] A indexable milling blade comprises a first cutting portion and a second cutting portion distributed in the length direction of the milling blade, the first cutting portion and the second cutting portion have the same outer contour; the first cutting portion comprises two main positioning surfaces distributed perpendicular to the thickness direction of the milling blade, and a through hole passes through the two main positioning surfaces as a mounting hole for the milling blade; the junction of the first cutting portion and the second cutting portion is a staggered structure having an offset in a direction perpendicular to the main positioning surfaces, the staggered structure comprises a first axial positioning surface located on the first cutting portion and a second axial positioning surface located on the second cutting portion; the projection of the second cutting portion after rotating 180° around the center of the staggered structure coincides with the first cutting portion; the first cutting portion comprises two cutting units arranged in a centrally symmetrical manner, and the cutting unit comprises a main cutting edge arranged parallel to the length direction of the milling blade.

[0010] Furthermore, the cutting unit also includes a corner cutting edge and a secondary corner cutting edge respectively connected to both ends of the main cutting edge.

[0011] Furthermore, the cutting unit further comprises a wiper edge connected to the corner cutting edge.

[0012] Furthermore, the wiper blade is an arc wiper blade.

[0013] Still further, the center of the cutting circle formed by the two main cutting edges of the first cutting portion is not on the connecting line of the two main cutting edges.

[0014] Furthermore, the first cutting portion and the second cutting portion have equal thickness.

[0015] Further, the surface of the first cutting portion opposite to the first axial positioning surface is a positioning end surface of the milling blade, and the positioning end surface is parallel to the first axial positioning surface.

[0016] A milling tool comprises a tool body, wherein the end of the tool body has a first clamping part and a second clamping part, a groove for embedding a milling blade is provided between the first clamping part and the second clamping part, and connecting holes are provided on the first clamping part and the second clamping part for installing a connecting part to position the milling blade.

[0017] Furthermore, the connecting piece is a locking screw.

[0018] Furthermore, the blade body is an integrally formed structure.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1) A total of four main cutting edges are designed on the milling insert. When the milling insert is put into cutting, two main cutting edges with unequal tooth pitches on the circumference participate in the cutting, while the other two main cutting edges are located within the cutting diameter. This unique cutting edge arrangement structure can be well applied to milling cutters with smaller cutting diameters. Under the condition of the same milling insert size, the minimum diameter of the milling cutter of the present invention is smaller than that of ordinary milling cutters, and is particularly suitable for milling processing of small and fine cavity parts.

[0021] 2) The milling blade is cut by two main cutting edges with unequal tooth pitches on the circumference each time, which can achieve the effect of reducing cutting vibration;

[0022] 3) When cutting, the milling insert has two main cutting edges whose rotation diameter on the milling tool is smaller than the cutting diameter, so as to avoid the two main cutting edges from participating in the cutting, thereby achieving the function of indexable and protecting the cutting edges;

[0023] 4) The four main cutting edges and four corner cutting edges undertake the main cutting tasks. The main cutting edge, corner cutting edge, secondary corner cutting edge, and wiper edge form the main cutting edge flank, corner cutting edge flank, secondary corner cutting edge flank, and wiper edge flank, which constitute the cutting flank angle during the cutting process and ensure the normal cutting process; the main cutting edge rake face provides a guide for chip control, and the wedge angle formed by the main cutting edge rake face and the main cutting edge flank face takes into account the sharpness and strength requirements of the blade. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a three-dimensional structural diagram of the milling insert described in Example 1;

[0025] Figure 2 It is a schematic diagram of the application of the milling insert in Example 1 and a top view of the milling tool described in Example 3;

[0026] Figure 3 is a three-dimensional structural diagram of the milling tool described in Example 3;

[0027] Figure 4 for Figure 3 Side view of the milling tool. DETAILED DESCRIPTION

[0028] In order to clearly illustrate the technical features of the present solution, the present technical solution is described in detail below through specific implementation methods and in conjunction with the accompanying drawings.

[0029] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present application is not limited to the specific embodiments disclosed below.

[0030] In addition, in the description of the present application, it should be understood that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0031] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0032] In the present application, unless otherwise clearly specified and limited, a first feature "above" or "below" a second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in an appropriate manner in any one or more embodiments or examples.

[0033] Example 1

[0034] like Figure 1 The indexable milling insert shown includes a first cutting portion 2 and a second cutting portion 3 distributed in the length direction of the milling insert. The first cutting portion 2 and the second cutting portion 3 have the same outer contours. The structure of the first cutting portion 2 is described below.

[0035] The first cutting portion 2 includes two main positioning surfaces 21 distributed perpendicular to the thickness direction of the milling blade, and a through hole 22 is formed between the two main positioning surfaces 21 as a mounting hole for the milling blade; the junction of the first cutting portion 2 and the second cutting portion 3 is a dislocation structure having an offset in a direction perpendicular to the main positioning surface, and the dislocation structure includes a first axial positioning surface ( Figure 1 The projection of the second cutting portion 3 after rotating 180° around the center of the offset structure completely overlaps with the first cutting portion 2.

[0036] The first cutting part 2 includes two cutting units arranged in a central symmetric manner, the cutting unit includes a main cutting edge 41 arranged parallel to the length direction of the milling blade, and also includes a corner cutting edge 42 and a secondary corner cutting edge 43 connected to both ends of the main cutting edge 41, and a wiper edge 44 is connected to the end of the corner cutting edge 42. In this embodiment, the wiper edge 44 is an arc wiper edge; the main cutting edge 41 and the corner cutting edge 42 undertake the main cutting task. The main cutting edge 41, the corner cutting edge 42, the secondary corner cutting edge 43 and the wiper edge 44 extend in the direction of the back face to form a main cutting edge back face 45, a corner cutting edge back face 46, a secondary corner cutting edge back face 47 (since this structure is not shown on the first cutting part, the number 47 is marked on the second cutting part) and a wiper edge back face 48, thereby forming a cutting back angle during the cutting movement, ensuring the normal progress of cutting.

[0037] The main cutting edge 41 extends in the rake face direction to form a main cutting edge rake face 49, which provides a guide for chip control and forms a wedge angle with the main cutting edge flank face 45, thereby taking into account both the sharpness and strength requirements of the blade.

[0038] like Figure 2 As shown, when the milling blade is installed on the tool for milling operation, when viewed in the direction perpendicular to the tool rotation axis, the dotted circle in the figure is a cutting circle A whose center is on the tool rotation axis and formed by the two main cutting edges 41 of the first cutting part 2. The center of the cutting circle is not on the vertical line connecting the two main cutting edges of the first cutting part 2 (at this time, the center may or may not be on the vertical line connecting the two main cutting edges of the second cutting part), that is, the two main cutting edges 41 are eccentric on the tool, and there is an effect of unequal tooth pitch on the circumference, which has a significant effect on reducing the tool milling vibration. Similarly, due to the existence of the offset structure, when the milling blade is reversed so that the second cutting part 3 is put into cutting, the two main cutting edges on the second cutting part 3 also have an eccentric anti-vibration effect on the tool.

[0039] also, Figure 2In the embodiment, when the first cutting part 2 is put into cutting, the two main cutting edges of the second cutting part 3 are in the cutting circle and have a distance S from the cutting circle, thereby protecting the two main cutting edges of the second cutting part 3 from participating in the cutting. After the two main cutting edges of the first cutting part 2 are worn, the two main cutting edges of the second cutting part 3 can be put into the cutting state by reversing the orientation of the milling blade, thereby realizing the indexable function of the blade.

[0040] In this embodiment, the first cutting portion 2 and the second cutting portion 3 have equal thickness; the surface on the first cutting portion 2 opposite to the first axial locating surface is the positioning end face 23 of the milling blade, and the positioning end face is parallel to the first axial locating surface; similarly, the surface on the second cutting portion 3 opposite to the second axial locating surface 31 is also the positioning end face of the milling blade, and the positioning end face is parallel to the second axial locating surface.

[0041] The main positioning surfaces 21 on the first cutting part and the second cutting part of the milling blade are four parallel planes, which are mainly used to position the milling blade in the normal direction of the main positioning surfaces; the positioning end surface 23, the first axial positioning surface and the second axial positioning surface 31 are mainly used to position the milling blade in the direction of the tool rotation axis.

[0042] The unique cutting edge design of the milling insert of the present invention can be well applied to milling tools with smaller cutting diameters. Under the same milling insert size, the minimum diameter of the milling tool is smaller than that of ordinary indexable milling tools, and can be applied to milling of small cavity parts.

[0043] Example 2

[0044] An indexable milling insert, still referring to Figure 1 , which includes a first cutting portion and a second cutting portion distributed in the length direction of the milling blade, and the first cutting portion and the second cutting portion have the same outer contour. The structure of the first cutting portion is described below.

[0045] The first cutting portion includes two main positioning surfaces distributed perpendicularly to the thickness direction of the milling blade, and a through hole is passed between the two main positioning surfaces as a mounting hole for the milling blade; the junction between the first cutting portion and the second cutting portion is a staggered structure having an offset in a direction perpendicular to the main positioning surfaces, and the staggered structure includes a first axial positioning surface located on the first cutting portion and a second axial positioning surface located on the second cutting portion; the projection of the second cutting portion after rotating 180° around the center of the staggered structure completely overlaps with the first cutting portion.

[0046] The first cutting part includes two cutting units arranged in a central symmetric manner. The cutting units include a main cutting edge arranged parallel to the length direction of the milling blade, and also include a corner cutting edge and a secondary corner cutting edge connected to both ends of the main cutting edge, and a wiper edge is connected to the end of the corner cutting edge; the main cutting edge and the corner cutting edge undertake the main cutting task. The main cutting edge, the corner cutting edge, the secondary corner cutting edge and the wiper edge extend in the direction of the back face to form the main cutting edge back face, the corner cutting edge back face, the secondary corner cutting edge back face and the wiper edge back face, thereby forming a cutting back angle during the cutting movement, ensuring the normal progress of cutting.

[0047] The main cutting edge extends in the rake face direction to form a main cutting edge rake face 18, which provides a guide for chip control and forms a wedge angle with the main cutting edge flank face, thereby taking into account both the sharpness and strength requirements of the insert.

[0048] refer to Figure 2 When the milling insert is installed on the tool for milling operation, the dotted circle in the figure is a cutting circle whose center is on the tool rotation axis and formed by the two main cutting edges of the first cutting part, and the center of the cutting circle is not on the vertical line between the two main cutting edges of the first cutting part (in this case, the center may or may not be on the vertical line between the two main cutting edges of the second cutting part), that is, the two main cutting edges are eccentric on the tool, and there is an effect of unequal tooth pitch on the circumference, which can have a significant effect on reducing the milling vibration of the tool. Similarly, due to the existence of the dislocation structure, when the milling insert is reversed and the second cutting part is put into cutting, the two main cutting edges on the second cutting part also have an eccentric anti-vibration effect on the tool.

[0049] also, Figure 2 When the first cutting part is engaged in cutting, the two main cutting edges of the second cutting part are within the cutting circle and are at a distance S from the cutting circle, thereby protecting the two main cutting edges of the second cutting part from participating in cutting. After the two main cutting edges of the first cutting part are worn, the milling insert can be turned around to put the two main cutting edges of the second cutting part in a cutting state, thereby realizing the indexable function of the insert.

[0050] In this embodiment, the first cutting portion and the second cutting portion have equal thickness; the surface on the first cutting portion opposite to the first axial locating surface is the positioning end face of the milling blade, and the positioning end face is parallel to the first axial locating surface; similarly, the surface on the second cutting portion opposite to the second axial locating surface is also the positioning end face of the milling blade, and the positioning end face is parallel to the second axial locating surface.

[0051] The difference between this embodiment and the first embodiment is that the wiper edge is a straight wiper edge.

[0052] Example 3

[0053] A kind of Figure 2 and Figure 3 The milling tool shown includes a tool body 5 and the milling blade 1 described in Example 1. The end of the tool body 5 has a first clamping portion 51 and a second clamping portion 52. A groove 53 is provided between the first clamping portion 51 and the second clamping portion 52 for the milling blade 1 to be embedded. Connecting holes 54 are provided on the first clamping portion 51 and the second clamping portion 52 for the connection member 6 to be installed to position the milling blade 1.

[0054] like Figure 4 As shown, in this embodiment, the connecting piece 6 is a locking screw, the connecting hole 54 is a threaded hole, and the cutter body 5 is an integrally formed structure. After the milling blade 1 is inserted into the groove 53 from the side, the locking screw is screwed into the connecting hole 54, so that the locking screw passes through the first clamping part connecting hole, the milling blade through hole and the second clamping part connecting hole in sequence. As the locking screw is twisted in the connecting hole, a tightening force is generated, causing the first clamping part 51 and the second clamping part 52 of the cutter body to undergo elastic deformation, firmly pressing the milling blade 1 and accurately positioning it in the groove 53, thereby ensuring the cutting performance of the milling tool.

[0055] Obviously, the above embodiments are merely examples for clearly illustrating the technical solutions of the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An indexable milling insert, characterized in that: It includes a first cutting part and a second cutting part distributed in the length direction of the milling blade, and the first cutting part and the second cutting part have the same outer contour; the first cutting part includes two main positioning surfaces distributed perpendicular to the thickness direction of the milling blade, and a through hole passes through the two main positioning surfaces as a mounting hole of the milling blade; the junction of the first cutting part and the second cutting part is a staggered structure with an offset in the direction perpendicular to the main positioning surface, and the staggered structure includes a first axial positioning surface located on the first cutting part and a second axial positioning surface located on the second cutting part; the projection of the second cutting part after rotating 180° around the center of the staggered structure coincides with the first cutting part; the first cutting part includes two cutting units arranged in a central symmetrical manner, and the cutting unit includes a main cutting edge arranged parallel to the length direction of the milling blade.

2. The indexable milling insert according to claim 1, characterized in that: The cutting unit also includes a corner cutting edge and a secondary corner cutting edge respectively connected to both ends of the main cutting edge.

3. The indexable milling insert according to claim 2, characterized in that: The cutting unit further includes a wiper edge connected to the corner cutting edge.

4. The indexable milling insert according to claim 3, characterized in that: The wiper blade is an arc wiper blade.

5. The indexable milling insert according to any one of claims 1 to 4, characterized in that: The center of a cutting circle formed by the two main cutting edges of the first cutting portion is not on a connecting line of the two main cutting edges.

6. The indexable milling insert according to claim 1, characterized in that: The first cutting portion and the second cutting portion have the same thickness.

7. The indexable milling insert according to claim 1, characterized in that: The surface of the first cutting portion opposite to the first axial positioning surface is the positioning end surface of the milling blade, and the positioning end surface is parallel to the first axial positioning surface.

8. A milling tool, characterized in that: The tool body comprises a first clamping part and a second clamping part at the end thereof, a groove for embedding a milling blade is provided between the first clamping part and the second clamping part, and connecting holes are provided on the first clamping part and the second clamping part for installing a connecting part to position the milling blade.

9. The milling tool according to claim 8, characterized in that The connecting piece is a locking screw.

10. The milling tool according to claim 8, characterized in that The knife body is an integrated structure.

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