阅读说明：本技术 一种球头铣刀 (Ball-end milling cutter ) 是由 都胡飞 占方伟 马志飞 蔡翔 陈冲 于 2021-09-07 设计创作，主要内容包括：本发明提供了一种球头铣刀,包括刀杆和连接在刀杆一端的球形刀头,球形刀头上设有切削结构,球形刀头的远离刀杆侧具有和刀杆中心线相交的中心端,切削结构包括设置于球形刀头的第一切削刃组和第二切削刃组,第一切削刃组和第二切削刃组均包括环绕中心端间隔排布的至少两切削齿,切削齿沿着球形刀头的表面朝远离中心端的方向延伸,第一切削刃组的切削齿的向心端比第二切削刃组的切削齿的向心端更为靠近中心端,第二切削刃组的切削齿数量多于第一切削刃组的切削齿数量。本发明的在球形刀头上设置大量的切削齿,可以满足高精度难加工模具的加工要求,越靠近中心端的切削齿的数量越少,有利于工件废料排出,提高加工质量。(The invention provides a ball-end milling cutter, which comprises a cutter bar and a spherical cutter head connected to one end of the cutter bar, wherein a cutting structure is arranged on the spherical cutter head, the side, far away from the cutter bar, of the spherical cutter head is provided with a central end intersected with the central line of the cutter bar, the cutting structure comprises a first cutting edge group and a second cutting edge group which are arranged on the spherical cutter head, the first cutting edge group and the second cutting edge group respectively comprise at least two cutting teeth which are distributed at intervals around the central end, the cutting teeth extend along the surface of the spherical cutter head towards the direction far away from the central end, the centripetal end of the cutting teeth of the first cutting edge group is closer to the central end than the centripetal end of the cutting teeth of the second cutting edge group, and the number of the cutting teeth of the second cutting edge group is more than that of the cutting teeth of the first cutting edge group. According to the invention, the spherical cutter head is provided with a large number of cutting teeth, so that the processing requirements of a high-precision difficult-to-process die can be met, the number of the cutting teeth closer to the central end is smaller, the discharge of workpiece waste is facilitated, and the processing quality is improved.)

1. The ball-end milling cutter comprises a cutter bar and a spherical cutter head connected to one end of the cutter bar, wherein a cutting structure is arranged on the spherical cutter head, the spherical cutter head is far away from the cutter bar side and is provided with a central end intersected with the central line of the cutter bar, the ball-end milling cutter is characterized in that the cutting structure comprises a first cutting edge group and a second cutting edge group which are arranged on the spherical cutter head, the first cutting edge group and the second cutting edge group respectively comprise at least two cutting teeth which are arranged around the central end at intervals, the cutting teeth extend along the surface of the spherical cutter head towards the direction far away from the central end, the centripetal end of the cutting teeth of the first cutting edge group is closer to the central end than the centripetal end of the cutting teeth of the second cutting edge group, and the number of the cutting teeth of the second cutting edge group is more than that of the cutting teeth of the first cutting edge group.

2. A ball nose mill as set forth in claim 1 wherein the number of cutting teeth of the second cutting edge set is an integer multiple of the number of cutting teeth of the first cutting edge set.

3. A ball nose mill as set forth in claim 1 wherein said cutting teeth of said first cutting edge set are equiangularly spaced about said central end, said cutting teeth of said first cutting edge set being connected to said central end; each cutting tooth of the second cutting edge set is arranged around the central end at equal angular intervals.

4. A ball nose mill as set forth in claim 3 wherein said cutting teeth of said second cutting edge set surround said first cutting edge set, said cutting teeth of each of said first cutting edge set integrally connecting said cutting teeth of said second cutting edge set, said cutting teeth of at least one of said second cutting edge set being disposed between two adjacent cutting teeth of said first cutting edge set.

5. The ball nose mill of claim 1, wherein the cutting teeth include a rake surface connected to the spherical insert surface, a land connected to a side of the rake surface remote from the spherical insert, a first relief surface connected to a side of the land remote from the rake surface, and a second relief surface connected between the first relief surface and the spherical insert surface.

6. A ball nose mill as set forth in claim 5, characterized in that the plate face of the rake face has a tool rake angle with respect to a direction perpendicular to the plate face of the land, the plate face of the first relief face has a first relief angle with respect to a direction parallel to the plate face of the land, the plate face of the second relief face has a second relief angle with respect to a direction parallel to the plate face of the land, the value of the second relief angle being greater than the values of the tool rake angle and the first relief angle.

7. A ball nose milling cutter as claimed in claim 6, wherein the rake angle of the tool is in the range of 3-20 °, the first relief angle is in the range of 5-25 °, and the second relief angle is in the range of 30-70 °.

8. A ball nose mill as claimed in claim 5, characterized in that the width of the land has a value in the range of 0.003-0.05 mm, and that the surface of the land and the surface of the spherical insert have a predetermined distance therebetween, which predetermined distance has a value in the range of 0.01-0.5 mm.

9. A ball nose mill as claimed in any one of claims 1-8, wherein the cutting structure further comprises a spherical micro-cutting edge structure provided at the central end, the spherical micro-cutting edge structure comprising at least two cutting micro-cutting edges arranged at intervals at an end surface of the central end.

10. The ball nose mill of claim 1, wherein the tool holder includes a body and a taper portion connected to an end of the body, an end of the taper portion remote from the body being connected to the ball-shaped tool bit, the taper portion converging in a direction toward the tool bit.

[ technical field ] A method for producing a semiconductor device

The invention belongs to the technical field of machining tools, and particularly relates to a ball-end milling cutter.

[ background of the invention ]

The prior art mold processing is often encountered with molds made of difficult-to-process materials, such as hard alloy molds, graphite molds and the like, and such molds are often complex curved surfaces and have high requirements on the precision and the smoothness of processed surfaces. At present, most of common ball end mills on the market are hard alloy coating cutters with 2-4-edge structures, so that the processing efficiency is low, and the cutting edges are quickly worn; most of the existing cutters only have two edges passing through the spherical center of the ball-end milling cutter, the spherical center is weak in structure, machining abrasion at the spherical center is fast, the cutter is poor in shape retention and short in service life, and machining requirements of high-precision difficult-to-machine dies cannot be met.

Therefore, it is necessary to provide a new ball end mill, which ensures high precision, high wear resistance and long service life of the machining tool.

[ summary of the invention ]

The invention aims to provide a ball-end milling cutter which can solve the technical problem that the processing requirements of a high-precision difficult-to-process die cannot be met in the related technology.

The technical scheme of the invention is as follows: the utility model provides a ball milling cutter, includes the cutter arbor and connects the spherical tool bit in cutter arbor one end, be equipped with cutting structure on the spherical tool bit, keeping away from of spherical tool bit the cutter arbor side have with the crossing center end of cutter arbor central line, cutting structure including set up in spherical tool bit's first cutting edge group and second cutting edge group, first cutting edge group with second cutting edge group all includes encircleing two at least cutting teeth that the center end interval was arranged, the cutting tooth is along spherical tool bit's surface is towards keeping away from the direction of center end extends, the centripetal end of the cutting tooth of first cutting edge group is than the centripetal end of the cutting tooth of second cutting edge group is more close to the center end, the cutting tooth quantity of second cutting edge group is more than the cutting tooth quantity of first cutting edge group.

Preferably, the number of cutting teeth of the second cutting edge group is integral multiple of the number of cutting teeth of the first cutting edge group.

Preferably, each of said cutting teeth of said first cutting edge set are arranged at equal angular intervals around said central end, each of said cutting teeth of said first cutting edge set being connected to said central end; each cutting tooth of the second cutting edge set is arranged around the central end at equal angular intervals.

Preferably, the cutting teeth of the second cutting edge set surround the outer side of the first cutting edge set, the cutting teeth of each first cutting edge set are integrally connected with the cutting teeth of the second cutting edge set, and at least one cutting tooth of the second cutting edge set is arranged between two adjacent cutting teeth in the first cutting edge set.

Preferably, the cutting tooth includes a rake surface connected to the spherical insert surface, a land connected to a side of the rake surface remote from the spherical insert surface, a first flank surface connected to a side of the land remote from the rake surface, and a second flank surface connected between the first flank surface and the spherical insert surface.

Preferably, a tool rake angle is formed between the plate surface of the rake surface and a direction perpendicular to the plate surface of the land, a first relief angle is formed between the plate surface of the first relief surface and a direction parallel to the plate surface of the land, a second relief angle is formed between the plate surface of the second relief surface and a direction parallel to the plate surface of the land, and the value of the second relief angle is greater than the values of the tool rake angle and the first relief angle.

Preferably, the front angle of the cutter ranges from 3 to 20 °, the first back angle ranges from 5 to 25 °, and the second back angle ranges from 30 to 70 °.

Preferably, the width of the margin ranges from 0.003mm to 0.05mm, a predetermined distance is provided between the surface of the margin and the surface of the spherical tool bit, and the predetermined distance ranges from 0.01 mm to 0.5 mm.

Preferably, the cutting structure further includes a spherical center micro-blade structure disposed at the central end, and the spherical center micro-blade structure includes at least two cutting micro-blades disposed at intervals on the end surface of the central end.

Preferably, the cutter bar comprises a cutter body and a cone connected to one end of the cutter body, one end of the cone far away from the cutter body is connected to the spherical cutter head, and the cone shrinks towards the direction close to the cutter head.

The invention has the beneficial effects that: set up first cutting edge group and second cutting edge group at spherical tool bit, and first cutting edge group and second cutting edge group all include around two at least cutting teeth that central point interval was arranged for be provided with a large amount of cutting teeth on spherical tool bit, owing to utilize a large amount of cutting teeth to process the work piece, can improve the feed speed of work piece in the course of working moreover, thereby improve machining efficiency. Meanwhile, the centripetal end of the cutting teeth of the first cutting edge group is closer to the central end than the centripetal end of the cutting teeth of the second cutting edge group, the number of the cutting teeth of the second cutting edge group is more than that of the cutting teeth of the first cutting edge group, so that the number of the cutting teeth closer to the central end on the spherical cutter head is less than that of the cutting teeth farther from the central end on the spherical cutter head, the number of the cutting teeth is in gradient distribution along the radial direction of the spherical cutter head, the interval between the adjacent cutting teeth closer to the central end on the spherical cutter head is larger than that between the adjacent cutting teeth farther from the central end on the spherical cutter head, the workpiece waste is favorably discharged from the interval between the cutting teeth on the spherical cutter head, the surface of the workpiece is prevented from being scratched by the workpiece waste, and the processing quality is improved. The spherical cutter head is provided with a large number of cutting teeth, so that the processing requirement of a high-precision difficult-to-process die can be met, and the processing efficiency is improved; meanwhile, the number of the cutting teeth which are closer to the central end is smaller, so that the workpiece waste is discharged from the cutting teeth on the spherical cutter head at intervals, the surface of the workpiece is prevented from being scratched by the workpiece waste, and the processing quality is improved.

[ description of the drawings ]

Fig. 1 is a schematic view of the overall structure of a ball end mill according to the present invention;

FIG. 2 is an enlarged view of a portion of FIG. 1;

FIG. 3 is a top view of a spherical cutting head of a ball milling cutter according to the present invention;

fig. 4 is a schematic cross-sectional view of a cutting edge in a ball end mill according to the present invention;

FIG. 5 is a schematic cross-sectional view of a ball center micro-blade structure of a ball end mill according to the present invention;

FIG. 6 is a micro-topography of a spherical center micro-blade structure in a ball milling cutter according to the present invention.

[ detailed description ] embodiments

The invention is further described with reference to the following figures and embodiments.

Referring to fig. 1 and 2, a ball milling cutter includes a cutter bar 1 and a spherical cutter head 2 connected to one end of the cutter bar 1, the spherical cutter head 2 is provided with a cutting structure 21, a side of the spherical cutter head 2 away from the cutter bar 1 is provided with a center end 22 intersecting with a center line of the cutter bar 1, the cutting structure 21 includes a first cutting edge group 211 and a second cutting edge group 212 arranged on the spherical cutter head 2, each of the first cutting edge group 211 and the second cutting edge group 212 includes at least two cutting teeth 214 arranged around the center end 22 at intervals, the cutting teeth 214 extend along a surface of the spherical cutter head 2 in a direction away from the center end 22, a centripetal end of each cutting tooth 214 of the first cutting edge group 211 is closer to the center end 22 than a centripetal end of each cutting tooth 214 of the second cutting edge group 212, and the number of the cutting teeth 214 of the second cutting edge group 212 is greater than the number of the cutting teeth 214 of the first cutting edge group 211.

The spherical cutter head 2 is provided with the first cutting edge group 211 and the second cutting edge group 212, and the first cutting edge group 211 and the second cutting edge group 212 respectively comprise at least two cutting teeth 214 which are arranged around the central end 22 at intervals, so that a large number of cutting teeth 214 are arranged on the spherical cutter head 2, and the feeding speed of a workpiece can be improved in the machining process due to the fact that the workpiece is machined by the large number of cutting teeth 214, and machining efficiency is improved. Meanwhile, the centripetal end of the cutting teeth 214 of the first cutting edge group 211 is closer to the central end 22 than the centripetal end of the cutting teeth 214 of the second cutting edge group 212, the number of the cutting teeth 214 of the second cutting edge group 212 is more than that of the cutting teeth 214 of the first cutting edge group 211, so that the number of the cutting teeth 214 on the spherical cutter head 2 closer to the central end 22 is less than that of the cutting teeth 214 on the spherical cutter head 2 farther from the central end 22, the number of the cutting teeth 214 is distributed in a gradient manner along the radial direction of the spherical cutter head 2, the interval between the adjacent cutting teeth 214 on the spherical cutter head 2 closer to the central end 22 is larger than that between the adjacent cutting teeth 214 on the spherical cutter head 2 farther from the central end 22, the discharge of the workpiece waste from the interval between the cutting teeth 214 on the spherical cutter head 2 is facilitated, the scratch of the surface of the workpiece is avoided, and the machining quality is improved. The machining requirements of a high-precision and difficult-to-machine die can be met and the machining efficiency is also improved by arranging a large number of cutting teeth 214 on the spherical cutter head 2; meanwhile, the smaller the number of the cutting teeth 214 closer to the center end 22, the more the work waste is discharged from the space between the cutting teeth 214 on the spherical cutter head 2, thereby preventing the work surface from being scratched by the work waste and improving the machining quality.

Referring to fig. 1, 2 and 3, the number of cutting teeth 214 of the second cutting edge group 212 is an integral multiple of the number of cutting teeth 214 of the first cutting edge group 211. In some embodiments of the present embodiment, the number of the cutting teeth 214 on the surface of the spherical cutter head 2 is distributed in a gradient manner along the radial direction of the spherical cutter head 2, the surface of the spherical cutter head 2 may be sequentially provided with 2 to 4 gradients from the central end to the outside, each gradient is provided with a cutting tooth 214, and the cutting teeth 214 with the same gradient may be used as a cutting edge group, the number of the cutting teeth 214 of the gradient on the spherical cutter head 2 closer to the central end 22 is smaller than the number of the cutting teeth 214 of the gradient on the spherical cutter head 2 farther from the central end 22, and the number of the cutting teeth 214 of each gradient increases in an integral multiple manner along the surface of the spherical cutter head 2 toward the direction far from the central end 22, which is beneficial for discharging the workpiece waste from the intervals between the cutting teeth 214 on the spherical cutter head 2, thereby avoiding the workpiece surface from being scratched by the workpiece waste and improving the machining quality. Preferably, in an embodiment, the cutting teeth 214 on the surface of the spherical cutter head 2 are arranged in three gradients, so that the surface of the spherical cutter head 2 has three cutting areas concentric with the central end, and the three cutting areas are arranged on the surface of the spherical cutter head 2 and are provided with the cutting teeth 214 arranged around the central end at equal angular intervals, which is beneficial to ensuring the machining precision of the ball-end milling cutter, and meanwhile, the high feeding rate of a workpiece can be realized in the machining process of the workpiece, so that the machining efficiency of the workpiece is greatly improved; the first cutting region 100 is disposed at the spherical cutting head 2 closest to the central end 22, and the first cutting region 100, the second cutting region 200, and the third cutting region 300 are sequentially arranged along the surface of the spherical cutting head 2 in a direction away from the central end 22. The first cutting zone 100 may be provided with 8 cutting teeth 214, the second cutting zone 200 may be provided with 16 cutting teeth 214, and the third cutting zone 300 may be provided with 32 cutting teeth 214, the number of cutting teeth 214 of the second cutting zone 200 being twice as many as the number of cutting teeth 214 of the first cutting zone 100, and the number of cutting teeth 214 of the third cutting zone 300 being twice as many as the number of cutting teeth 214 of the second cutting zone 200. It is understood that the first cutting edge group 211 and the second cutting edge group 212 are not particularly limited to the cutting teeth 214 with a certain gradient, as long as the centripetal end of the cutting teeth 214 of the first cutting edge group 211 is closer to the central end 22 than the centripetal end of the cutting teeth 214 of the second cutting edge group 212, and the number of the cutting teeth 214 of the second cutting edge group 212 is greater than the number of the cutting teeth 214 of the first cutting edge group 211, for example, for reference, when the first cutting edge group 211 is only the combination of the cutting teeth 214 of the first cutting region 100, the second cutting edge group 212 may be the combination of the cutting teeth 214 of the second cutting region 200 and the third cutting region 300; when the first cutting edge group 211 is a combination of the cutting teeth 214 of the first and second cutting regions 100 and 200, the second cutting edge group 212 may be a combination of the cutting teeth 214 of the third cutting region 300. In other embodiments of this embodiment, the number of cutting teeth 214 of the first cutting region 100 may be selected within a range of 2-30 according to actual needs, and the number of cutting teeth 214 of the second cutting region 200 and the third cutting region 300 may be increased by two times, three times, four times, or other integer multiples, such as: the first cutting zone 100 may be provided with 4 cutting teeth 214, the second cutting zone 200 may be provided with 12 cutting teeth 214, and the third cutting zone 300 is provided with 36 cutting teeth 214.

Referring to fig. 3, the cutting teeth 214 of the first cutting edge group 211 are arranged around the central end 22 at equal angular intervals, and the cutting teeth 214 of the first cutting edge group 211 are connected to the central end 22; the cutting teeth 214 of the second cutting edge set 212 are equally angularly spaced around the central end 22. The cutting teeth 214 of the second cutting edge set 212 surround the outer sides of the first cutting edge set 211, the cutting teeth 214 of each first cutting edge set 211 are integrally connected with the cutting teeth 214 of one second cutting edge set 212, and at least one cutting tooth 214 of the second cutting edge set 212 is arranged between two adjacent cutting teeth 214 in the first cutting edge set 211. In some embodiments of the present embodiment, the flute 23 is formed by the interval between adjacent cutting teeth 214 of the same cutting edge group, each cutting tooth 214 of the first cutting edge group 211 and each cutting tooth 214 of the second cutting tooth 214 are arranged around the central end 22, and the center line of the tool holder 1 is located in the plane where the extending direction of the cutting tooth 214 is located, so that there is no bend in the cutting tooth 214 at the view point of fig. 3, which is beneficial for smooth flow of the workpiece waste in the flute 23. One end of the cutting teeth 214 of the first cutting edge group 211 is connected to the central end 22, the other end of the cutting teeth 214 of the first cutting edge group 211 extends in a direction away from the central end 22 along the surface of the spherical cutter head 2, when the first cutting edge group 211 is only the combination of the cutting teeth 214 of the first cutting region 100 and the second cutting edge group 212 is the combination of the cutting teeth 214 of the second cutting region 200 and the third cutting region 300, the interval angle between the cutting teeth 214 of the first cutting edge group 211 is 45 °, the interval angle between the cutting teeth 214 of the second cutting edge group 212 is 11.25 °, and the lengths of the cutting teeth 214 of the second cutting edge group 212 are not equal, the cutting teeth 214 of the second cutting edge group 212 include short cutting teeth 214 and long cutting teeth 214, preferably, the length of the short cutting teeth 214 of the second cutting edge group 212 is equal to the length of the cutting teeth 214 of the first cutting edge group 211, and the length of the long cutting teeth 214 of the second cutting edge group 212 is equal to the length of the short cutting teeth 214 of the second cutting edges of the second cutting edge group 212 The cutting teeth 214 of the first cutting edge group 211 and the second cutting edge group 212 are arranged in a manner that the cutting teeth 214 are formed on the surface of the spherical cutter head 2. Meanwhile, the spacing angle between the cutting teeth 214 of the first cutting edge group 211 is larger than that between the cutting teeth 214 of the second cutting edge group 212, and the position where the workpiece waste is generated in the processing process of the ball-end milling cutter is the position where the spherical cutter head 2 is close to the central end 22 at most, so that the width of the chip groove 23 closer to the central end 22 is larger than that of the chip groove 23 farther from the central end 22, the reasonable distribution of the width of the chip groove 23 is realized, the workpiece waste is favorably flowed to the second cutting edge group 212 from the first cutting edge group 211, the situation that the workpiece waste close to the central end 22 is not smoothly discharged is avoided, and the surface of the workpiece is prevented from being scratched by the workpiece waste. Moreover, the long cutting teeth 214 in the second cutting edge group 212 are connected with one end of the cutting teeth 214 in the first cutting edge group 211 far from the central end 22, and one long cutting tooth 214 is arranged between every two short cutting teeth 214 in the two cutting edge groups, so that a plurality of chip grooves 23 are formed on the surface of the spherical cutter head 2, and the workpiece waste is divided on the surface of the spherical cutter head 2. In other embodiments of the present embodiment, according to actual needs, the center line of the tool holder 1 and the plane in which the cutting teeth 214 extend may not coincide with each other, and the cutting teeth 214 are curved in the view of fig. 3, while the chip flutes 23 are formed between the cutting teeth 214 on the surface of the spherical cutter head 2. The length of the cutting tooth 214 of the first cutting edge group 211, the length of the short cutting tooth 214 in the second cutting edge group 212, and the length of the long cutting tooth 214 in the second cutting edge group 212 may also be set according to actual needs, such as: the short cutting teeth 214 in the second cutting edge set 212 are twice as long as the cutting teeth 214 of the first cutting edge set 211, and the long cutting teeth 214 in the second cutting edge set 212 are twice as long as the short cutting teeth 214 in the second cutting edge set 212. The angle of the interval between the cutting teeth 214 of the first cutting edge group 211 and the angle of the interval between the cutting teeth 214 of the second cutting edge group 212 may be set according to actual needs, such as: when the interval angle between the respective cutting teeth 214 of the first cutting edge group 211 is 90 °, the interval angle between the respective cutting teeth 214 of the second cutting edge group 212 is 10 °; when the interval angle between the respective cutting teeth 214 of the first cutting edge group 211 is 60 °, the interval angle between the respective cutting teeth 214 of the second cutting edge group 212 is 15 °.

Referring to fig. 3 and 4, the cutting tooth 214 includes a rake face 2141 connected to the surface of the spherical bit 2, a land 2142 connected to the side of the rake face 2141 remote from the spherical bit 2, a first flank face 2143 connected to the side of the land 2142 remote from the rake face 2141, and a second flank face 2144 connected between the first flank face 2143 and the surface of the spherical bit 2. A tool rake angle α is formed between the plate surface of the rake surface 2141 and a direction perpendicular to the plate surface of the land 2142, a first relief angle β is formed between the plate surface of the first flank surface 2143 and a direction parallel to the plate surface of the land 2142, a second relief angle γ is formed between the plate surface of the second flank surface 2144 and a direction parallel to the plate surface of the land 2142, and the value of the second relief angle γ is larger than the values of the tool rake angle α and the first relief angle β. In some embodiments of the present embodiment, the extending direction of the plate surface of the rake surface 2141 and the extending direction of the plate surface of the second relief surface 2144 intersect at a side away from the surface of the spherical tool bit 2, the distance between the side of the rake surface 2141 away from the surface of the spherical tool bit 2 and the surface of the spherical tool bit 2 is greater than the distance between the side of the second relief surface 2144 away from the surface of the spherical tool bit 2 and the surface of the spherical tool bit 2, the land 2142 may be a plane, the plane where the land 2142 is located is tangent to the surface of the spherical tool bit, the length direction of the land 2142 is parallel to the extending direction of the cutting teeth 214, the included angle between the rake surface 2141 and the surface of the spherical tool bit 2 is an obtuse angle, and the included angle between the second relief surface 2144 and the surface of the spherical tool bit 2 is an obtuse angle. Preferably, in an embodiment, an included angle between the rake surface 2141 and the surface of the spherical cutter head 2 is equal to an included angle between the second relief surface 2144 and the surface of the spherical cutter head 2, so that the transmission of the collision force generated when the cutting tooth 214 contacts the workpiece in the cutting tooth 214 is more uniform, the damage of the cutting tooth 214 due to collision is avoided, and the service life of the cutting tooth 214 is prolonged; the surface of the margin 2142 is tangent to the surface of the spherical cutting head 2, and the surface of the margin 2142 has a width that increases the contact area of the margin 2142 with the workpiece during machining, improves the wear resistance of the margin 2142, and increases the effective cutting area of the tool. The second relief angle γ is greater than the first relief angle β, and the second relief angle γ is greater than the tool rake angle α, it can be understood that, when the cutting tooth 214 processes a workpiece, the rake surface 2141 side of the cutting tooth 214 first contacts the workpiece, and workpiece waste generated by the rake surface 2141 processing the workpiece flows into the chip removal groove 23 after passing through the first relief surface 2143 and the second relief surface 2144, and the larger γ angle increases the chip containing space and improves the smoothness of chip removal. In other embodiments of the present embodiment, the included angle between the rake surface 2141 and the surface of the spherical tool bit 2 may be smaller than the included angle between the second relief surface 2144 and the surface of the spherical tool bit 2; the included angle between the rake surface 2141 and the surface of the spherical cutter head 2 may be a right angle or an acute angle, and the included angle between the second flank surface 2144 and the surface of the spherical cutter head 2 may be a right angle or an acute angle.

Referring to fig. 3 and 4, the rake angle of the cutter ranges from 3 to 20 °, the first relief angle ranges from 5 to 25 °, and the second relief angle ranges from 30 to 70 °. The width of the margin 2142 ranges from 0.003 to 0.05mm, the surface of the margin 2142 has a predetermined distance H from the surface of the spherical cutting head 2, and the predetermined distance ranges from 0.01 to 0.5 mm. In some embodiments of the present embodiment, the α angle may be 3 °, 4 °, 10 °, 20 °, etc., the β angle may be 5 °, 10 °, 15 °, 25 °, etc., and the γ angle may be 30 °, 35 °, 42 °, 70 °, etc., and a larger γ angle increases the chip accommodating space, thereby improving the smoothness of chip removal; the width of the margin 2142 may have a value of 0.003mm, 0.005mm, 0.02mm, 0.05mm, etc., the predetermined distance H between the face of the margin 2142 and the surface of the spherical bit 2 may be 0.01, 0.02, 0.2, 0.5, etc., and the smaller width of the margin 2142 may increase the contact area of the margin 2142 with the workpiece, thereby enhancing the wear resistance of the margin 2142. In other embodiments of this embodiment, the α angle may be any value between 3-20 °, the β angle may be any value between 5-25 °, the γ angle may be any value between 30-70 °, the width of the margin 2142 may be any value between 0.003-0.05 mm, and the predetermined distance H may be any value between 0.01-0.5 mm, according to actual needs.

Referring to fig. 3, 5 and 6, the cutting structure 21 further includes a spherical micro blade structure 213 disposed at the central end 22, and the spherical micro blade structure 213 includes at least two cutting micro blades 2131 disposed at intervals at an end surface of the central end 22. In some embodiments of the present embodiment, the central end 22 is spherical, and the diameter of the central end 22 may be any value between 0.04 mm and 0.2mm, the central end 22 is solid, a plurality of cutting micro blades 2131 are arranged on a side of the central end 22 away from the spherical cutter head 2 at intervals, the cutting micro blades 2131 on the central end 22 may be divided into 12 groups arranged at equal intervals, and the cutting micro blades 2131 of each group of cutting micro blades are wavy. Preferably, the cutting micro blades 2131 on the central end 22 are processed in a mode of laser processing dermatoglyph, the micron-sized cutting micro blades 2131 are processed through laser, specifically, the spherical tool bit 2 is placed into laser processing equipment, laser is emitted and irradiated to one side to be processed of the central end 22 of the spherical tool bit 2, a large number of cutting micro blades 2131 are uniformly distributed on one side, away from the spherical tool bit 2, of the central end 22 after the laser processing is completed, wherein the diameter Da of a light spot irradiated to one side to be processed of the central end 22 through the laser is 14.74um, the laser etching depth La is 12.46um, and through the mode of laser processing, while the spherical shape of the central end 22 is not damaged, the micron-sized cutting blades are added, the cutting capability of the spherical center of the cutter is ensured, and the structure is more wear-resistant. Adjacent cutting micro blades 2131 in each group of cutting micro blades 2131 on the central end 22 are connected, so that the central end 22 forms a solid chip-breaker-free structure, the structural strength of the central end 22 is increased, the shape retention performance of the ball-end milling cutter is better, the ball-end milling cutter is more wear-resistant, and the service life of the ball-end milling cutter is prolonged.

Referring to fig. 1 and 2, the tool holder 1 includes a tool body 11 and a tapered portion 12 connected to an end of the tool body 11, wherein an end of the tapered portion 12 remote from the tool body 11 is connected to the spherical tool bit 2, and the tapered portion 12 is tapered in a direction toward the tool bit. In some embodiments of the present invention, the tool bar 1 is a phi 4-8 bar material, the tool bar 1 is made of a hard alloy material, and the tool bar 1 is used outside and on a CNC processing machine to drive the ball-end mill to move and rotate; the spherical cutter head 2 is connected with the cutter bar 1 through a brazing method, and the spherical cutter head 2 is made of superhard materials such as polycrystalline diamond (PCD), Polycrystalline Cubic Boron Nitride (PCBN) and metal ceramics. Preferably, in an embodiment, the spherical cutter head 2 is polycrystalline diamond, the cutter bar 1 is a cemented carbide bar with a diameter of 4, the grooved spherical cutter head 2 and the tapered part 12 on the cutter bar 1 are prepared by a slow wire electric machining or numerical control grinding machine grinding method, and then materials are removed by laser processing to form the cutting teeth 214 and the chip grooves 23, at this time, the cutting teeth 214 and the spherical cutter head 2 are integrally arranged, so that the stability of connection between the cutting teeth 214 and the spherical cutter head 2 is enhanced.

While the foregoing is directed to embodiments of the present invention, it will be understood by those skilled in the art that various changes may be made without departing from the spirit and scope of the invention.