CN211413804U

CN211413804U - Milling cutter

Info

Publication number: CN211413804U
Application number: CN201922372049.0U
Authority: CN
Inventors: 岳国汉
Original assignee: Individual
Current assignee: Shenzhen Muji Superhard Technology Co Ltd
Priority date: 2019-12-25
Filing date: 2019-12-25
Publication date: 2020-09-04
Anticipated expiration: 2029-12-25

Abstract

The utility model discloses a milling cutter, which comprises a cutter handle; the cutter head is arranged at one end of the cutter handle; first cutting blade, first cutting blade is protruding to be located the lateral wall of tool bit, first cutting blade is equipped with a plurality ofly, and is a plurality of first cutting blade is followed the circumference interval of tool bit is arranged, first cutting blade is followed the length direction of milling cutter extends the setting, first cutting blade deviates from one side of tool bit has first cutting edge, first cutting edge has seted up a plurality of first grooves of dodging along its length direction. The first smoothing blade is convexly arranged on the outer side wall of the cutter head, the first smoothing blade extends along the length direction of the milling cutter and is clamped between the two adjacent first cutting blades, and one side, deviating from the cutter head, of the first smoothing blade is provided with a first smoothing edge. The utility model discloses aim at changing the structure of blade to increase milling cutter's cutting strength.

Description

Milling cutter

Technical Field

The utility model relates to a milling process technical field, in particular to milling cutter.

Background

The milling cutter is a rotary cutter consisting of one or more blades, and when the milling cutter works, each cutter tooth sequentially and intermittently cuts off the allowance of a workpiece, and the milling cutter is mainly used for milling planes, contour cavities, space curved surfaces, special curves and the like on a milling machine tool. In the numerical control milling process, because the contact surface of the existing milling cutter blade and a workpiece is a smooth surface, the friction coefficient of the blade and the workpiece is small while the milling cutter rotates at a high speed, and particularly when some workpieces with smooth contact surfaces are processed, the cutting strength of the blade is weak, and the expected cutting effect cannot be achieved.

The above is only for the purpose of assisting understanding of the technical solutions of the present application, and does not represent an admission that the above is prior art.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a milling cutter aims at changing the structure of blade to increase milling cutter's cutting strength.

In order to achieve the above object, the utility model provides a milling cutter, include: a knife handle;

the cutter head is arranged at one end of the cutter handle;

first cutting blade, first cutting blade is protruding to be located the lateral wall of tool bit, first cutting blade is equipped with a plurality ofly, and is a plurality of first cutting blade is followed the circumference interval of tool bit is arranged, first cutting blade is followed the length direction of milling cutter extends the setting, just first cutting blade deviates from one side of tool bit has first cutting edge, first cutting edge has seted up a plurality of first grooves of dodging along its length direction.

The first smoothing blade is convexly arranged on the outer side wall of the cutter head, the first smoothing blade extends along the length direction of the milling cutter and is clamped between the two adjacent first cutting blades, and one side, deviating from the cutter head, of the first smoothing blade is provided with a first smoothing edge.

Optionally, the first smoothing blade is provided with a plurality of first smoothing blades, and the plurality of first smoothing blades are arranged at intervals along the circumferential direction of the cutter head.

Optionally, each of the first smoothing blades and one of the first cutting blades are alternately disposed on an outer sidewall of the cutter head.

Optionally, a chip groove is formed between the first smoothing insert and the first cutting insert adjacent to the first smoothing insert, the chip groove includes a first side wall and a second side wall extending along a length direction of the milling cutter, and a distance between the first side wall and the second side wall gradually increases along a radially outward direction of the cutter head.

Optionally, the spacing between the first sidewall and the second sidewall is 0.1mm-1.0 mm.

Optionally, the first cutting insert is arranged in a helical configuration along a circumference of the cutting head.

Optionally, the helix angle of the first cutting insert is 45 ° to 85 °.

Optionally, the shortest distance between two adjacent first cutting blades is 1.5mm-5.0 mm.

Optionally, the milling cutter further comprises: the second cutting blades are arranged on the outer edge of the end face of one end, far away from the cutter handle, of the cutter head, a plurality of the second cutting blades are arranged at intervals along the circumferential direction of the cutter head, the second cutting blades extend along the radial direction of the cutter head, one side, far away from the cutter head, of each second cutting blade is provided with a second cutting edge, and a plurality of second avoiding grooves are formed in the length direction of each second cutting edge;

the second light trimming blade is arranged at the outer edge of the end face of one end, far away from the cutter handle, of the cutter head, the second light trimming blade extends along the radial direction of the cutter head and is clamped between two adjacent second cutting blades, and a first light trimming edge is arranged on one side, far away from the cutter head, of the second light trimming blade.

Optionally, the tool holder is of a columnar structure, and the outer diameter of the tool holder is 2mm-10 mm; and/or the tool bit is a cutting piece made of a superhard composite material.

The utility model discloses technical scheme's milling cutter includes handle of a knife, tool bit, first cutting blade and first smoothing blade, and the handle of a knife plays fixed effect, and the one end and the tool bit of handle of a knife are connected, and first cutting blade and the equal protruding lateral wall of locating the tool bit of smoothing blade, and extend the setting along milling cutter's length direction, and first cutting blade has arranged a plurality ofly along the circumference direction interval of tool bit, and first smoothing blade presss from both sides and locates between the two adjacent first cutting blades. The first cutting blade is used for cutting the workpiece, and the first smoothing blade is used for polishing the workpiece, so that the smoothness of the workpiece is improved. Specifically, the first cutting blade is provided with a first cutting edge, and at least part of the first cutting edge is provided with a plurality of first avoidance grooves along the length direction of the first cutting edge; first smoothing blade has first smoothing sword, and specifically, first smoothing sword is smooth structure setting, is convenient for polish the rough surface of work piece. When the polishing machine is used, the cutter handle is fixed on the machine tool, and the first cutting blade and the first smoothing blade on the cutter head respectively cut and polish a workpiece. It can be understood that by providing the first avoiding groove on the first cutting edge, the friction coefficient between the first cutting insert and the workpiece can be increased, thereby achieving the purpose of increasing the cutting strength of the milling cutter.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

Fig. 1 is a schematic structural view of an embodiment of the milling cutter of the present invention;

FIG. 2 is an enlarged view of the cutting head of FIG. 1;

fig. 3 is an enlarged view of the first cutting insert of fig. 2;

fig. 4 is an enlarged view of the first wiper blade of fig. 2.

The reference numbers illustrate:

reference numerals	Name (R)	Reference numerals	Name (R)
				100	Milling cutter	131	First cutting edge
110	Knife handle	140	First smoothing blade
				120	Cutter head	141	First smoothing edge
130	First cutting blade	150	Chip groove
				132	First avoiding groove	170	Second smoothing blade
160	Second cutting blade

The objects, features and advantages of the present invention will be further described with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that all the directional indicators (such as upper, lower, left, right, front and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indicator is changed accordingly.

In the present application, unless expressly stated or limited otherwise, the terms "connected" and "fixed" are to be construed broadly, e.g., "fixed" may be fixedly connected or detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In addition, the descriptions related to "first", "second", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicit ly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and/or" appearing throughout is to include three juxtapositions, exemplified by "A and/or B," including either the A or B arrangement, or both A and B satisfied arrangement. In addition, the technical solutions in the embodiments may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should not be considered to exist, and is not within the protection scope of the present invention.

The utility model provides a milling cutter 100

As shown in fig. 1 to 4, in the embodiment of the present invention, the milling cutter 100 includes:

a knife handle 110;

the cutter head 120 is arranged at one end of the cutter handle 110;

the first cutting blade 130 is convexly arranged on the outer side wall of the cutter head 120, the first cutting blade 130 is provided with a plurality of first cutting blades 130 which are arranged along the circumferential direction of the cutter head 120 at intervals, the first cutting blade 130 is arranged along the length direction of the milling cutter in an extending manner, one side of the first cutting blade 130 departing from the cutter head 120 is provided with a first cutting edge 131, and the first cutting edge 131 is provided with a plurality of first avoiding grooves 132 along the length direction.

The first smoothing blade 140 is disposed on an outer side wall of the cutter head 120 in a protruding manner, the first smoothing blade 140 extends along a length direction of the milling cutter and is clamped between two adjacent first cutting blades 130, and a first smoothing edge 141 is disposed on a side of the first smoothing blade 140 away from the cutter head 120.

The tool holder 110 is a long-strip columnar structure, and the diameter of one end of the tool holder 110 close to the tool bit 120 is smaller than that of one end of the tool holder 110 far away from the tool bit 120. That is to say that the diameter of handle of a knife 110 is reduced to the one end that is close to tool bit 120 by the one end of keeping away from tool bit 120 gradually, and tool bit 120 is connected in the less one end of handle of a knife 110 diameter, and handle of a knife 110 wherein has one end to be the setting of inclined plane structure, can provide bigger cutter relieving space when the inclined plane sets up first cutting edge 131, avoids handle of a knife 110 and work piece too much contact, causes the work piece to damage. The whole structure of the tool apron is larger than that of the tool head 120 and is used for being connected with a machine tool. The tool bit 120 has a mounting surface and a first cutting edge 131, the mounting surface of the tool bit 120 is connected to the end of the tool apron with a smaller diameter, the outer side wall of the tool bit 120 is a bearing surface for bearing the first cutting blade 130 and the first dressing blade 140, the first cutting blade 130 and the first dressing blade 140 are convexly arranged on the bearing surface and extend along the direction departing from the bearing surface, that is, the first cutting blade 130 and the first dressing blade 140 protrude a certain height away from the bearing surface for contacting with a workpiece and machining and grinding the workpiece.

The first cutting blade 130 is provided with a first cutting edge 131 (the side for processing the workpiece) on the side away from the bearing surface, the first cutting edge 131 is provided with a first avoiding groove 132, that is, the first cutting edge 131 is serrated, specifically, the side of the first cutting edge 131 away from the bearing surface is provided with one or more serrations (the first avoiding groove 132) along the length of the first cutting edge 131 (the length direction of the tool holder 110), the plurality of first avoiding grooves 132 are arranged at intervals, and the first avoiding groove 132 is wide at the top and narrow at the bottom and is arranged in a triangular pyramid structure, the side of the first cutting blade 130 for processing the workpiece is designed to enhance the strength of the first cutting blade 130 during processing, that is, when the workpiece contacts with the first cutting blade 130, because of the design of the serration structure of the first cutting blade 130, the friction coefficient of the first cutting blade 130 with the workpiece is increased, even if a smoother workpiece is processed, and a better processing effect can be achieved.

The utility model discloses technical scheme's milling cutter 100 includes handle of a knife 110, tool bit 120, first cutting blade 130 and first smoothing blade 140, handle of a knife 110 plays fixed effect, the one end and the tool bit 120 of handle of a knife 110 are connected, first cutting blade 130 and the equal protruding lateral wall of locating tool bit 120 of first smoothing blade 140, and extend the setting along milling cutter's length direction, first cutting blade 130 has arranged a plurality ofly along the circumference direction interval of tool bit 120, first smoothing blade 140 presss from both sides and locates between two adjacent first cutting blades 130. The first cutting blade 130 is used to cut the workpiece and the first wiper blade 140 is used to polish the workpiece to increase the smoothness of the workpiece. Specifically, the first cutting blade 130 has a first cutting edge 131, and at least a portion of the first cutting edge is provided with a plurality of first avoiding grooves 132 along a length direction thereof, it can be understood that the first cutting edge has a saw-tooth structure, so that a contact area between the first cutting blade 130 and the workpiece can be increased, and cutting strength can be increased; the first wiper blade 140 has a first wiper edge 141, and specifically, the first wiper edge 141 is a smooth structure, which facilitates polishing of a rough surface of a workpiece. In use, the shank is secured to a machine tool, and the first cutting blade 130 and the first wiper blade 140 on the tool tip cut and polish a workpiece, respectively. It can be understood that by providing the first avoiding groove 132 on the first cutting edge 131, the friction coefficient between the first cutting insert and the workpiece can be increased, thereby achieving the purpose of increasing the cutting strength of the milling cutter.

Optionally, a plurality of the first wiper blades 140 are provided, and the plurality of the first wiper blades 140 are arranged at intervals along the circumferential direction of the cutter head 120.

The first smoothing edge 141 of the first smoothing blade 140 is provided with a smooth structure at the contact position with the workpiece, the first smoothing edge 141 is used for increasing the smoothness of the workpiece, because the first cutting blade 130 is serrated, and the workpiece is relatively rough after the first cutting edge 131 of the first cutting blade 130 is the workpiece, a plurality of first smoothing blades 140 are additionally arranged on the bearing surface, the first smoothing blade 140 is arranged between the two first cutting blades 130, the first smoothing blade 140 and the first cutting blade 130 are positioned on the same horizontal plane, and the first smoothing blade 140 extends along the length direction of the tool bit 120. That is, the lengths of the first wiper blade 140 and the first cutting blade 130 are equal, and since the tool head 120 rotates during the first cutting edge 131, the first wiper blade 141 can machine the workpiece at the same position after the first cutting edge 131 of the first cutting blade 130 is machined, and since the first wiper blade 140 is smooth, the roughness of the workpiece can be reduced when the first wiper blade 140 machines the workpiece.

Optionally, each of the first wiper blades 140 and the first cutting blades 130 are alternately disposed on an outer sidewall of the cutter head 120.

The first plurality of wiper blades 140 are spaced apart from the first plurality of cutting blades 130, each wiper blade 140 is disposed between two adjacent first cutting blades 130, and the first plurality of wiper blades are alternately spaced apart from the first plurality of cutting blades, respectively. To ensure the uniformity of the processed workpiece, the first wiper blade 140 and the first cutting blade 130 have the same length and the same height, so that the first cutting blade 130 and the first wiper edge 141 process the same portion of the workpiece, thereby achieving the purpose of increasing the smoothness of the workpiece. While the angle of inclination of the first wiper edge 141 to the first cutting insert 130 should be kept the same.

Optionally, a chip groove 150 is formed between the first smoothing insert 140 and the first cutting insert 130 adjacent to the first smoothing insert, the chip groove 150 includes a first side wall and a second side wall extending along a length direction of the milling cutter, and a distance between the first side wall and the second side wall gradually increases in a radially outward direction of the cutter head.

The chip discharge groove 150 is arranged to further break off longer chips because the first cutting edge 131 of the workpiece can be performed by both the first cutting insert 130 and the first wiper insert 140, and more chips are generated, and the first cutting edge 131 is too long and scratches the surfaces of the first cutting insert 130, the first wiper insert 140 and the workpiece. Specifically, the first side wall is a side wall of the first cutting blade facing the first smoothing blade, and the second side wall is a side wall of the first smoothing blade facing the first smoothing blade, and the distance between the first side wall and the second side wall gradually increases along the radial direction of the tool bit, that is, the chip discharge groove 150 is of a structure with a large upper part and a small lower part and is arranged in a V-shaped structure, so that the chips can conveniently fall into the chip discharge groove 150 and can effectively store part of the chips, and meanwhile, the chips can be discharged from two sides of the chip discharge groove 150, and the integrity of the first cutting blade 130, the first smoothing blade 140 and the workpiece is ensured.

In this embodiment, the distance between the first sidewall and the second sidewall is 0.1mm to 1.0 mm.

Since the first smoothing blade 140 and the first cutting blade 130 are disposed at an interval and both can be used for processing a workpiece, the first smoothing blade 140 is used for processing a relatively rough workpiece processing surface processed by the first cutting blade 130, and of course, the first smoothing blade 140 can also process a workpiece by itself. The first side wall and the second side wall are respectively arranged on the first cutting blade and the first smoothing blade, so that the distance between the first side wall and the second side wall is set to be 0.1mm-1.0mm in order to ensure the processing precision, and better cutting effect and polishing effect can be achieved.

In this embodiment, the first cutting insert 130 is disposed in a spiral configuration along the circumferential direction of the cutting head 120, and the spiral angle is 45 ° to 85 °.

Because the cutter head 120 is of a cylindrical structure, the first cutting blade 130 is spirally arranged along the circumferential direction of the cutter head 120, that is, the cutting edge of the first cutting blade 131 has a certain bending radian, so that the first cutting blade 130 does not contact with a workpiece at the same time during machining, the cutter blade is prevented from being broken, the spiral angle of the first cutting blade 130 is 45-85 degrees, the strength of the first cutting blade 131 during machining of the first cutting blade 130 can be ensured within the range, and the first cutting blade 130 can be prevented from contacting with the workpiece at the same time, so that the first cutting blade 130 is prevented from being broken. Of course, the angles of the spirals of the first cutting blades 130 are the same and are arranged towards the same circumferential direction, and the first wiper blade 140 and the first cutting blade 130 have substantially similar structures, and are not described herein again.

In this embodiment, the shortest distance between two adjacent first cutting blades 130 is 1.5mm to 5.0 mm.

The plurality of first cutting blades 130 are uniformly distributed on the bearing surface (the outer side wall of the tool bit 120) in the circumferential direction, so that the stability of the bearing surface during machining can be enhanced, the stress of a workpiece during machining is uniform, the stability and the smoothness of the workpiece during machining are improved, the first cutting edges 131 are more uniformly distributed, the plurality of first cutting blades 130 are uniformly distributed on the bearing surface, the first cutting blades have a certain thickness, the shortest distance between every two adjacent first cutting blades 130 is the distance between the two mutually-oriented side surfaces of the two adjacent first cutting blades, specifically, the distance is 1.5mm-5mm, a chip discharge groove 150 is formed in the middle of each first cutting blade, the two adjacent first cutting blades 130 keep a certain distance, the chip discharge function of the chip discharge groove 150 can be improved, and the surface of the workpiece is prevented from being scratched.

In this embodiment, the milling cutter 100 further includes:

the second cutting blade 160 is arranged at the outer edge of the end face of one end of the tool bit 120, which is far away from the tool holder 110, a plurality of second cutting blades 160 are arranged at intervals along the circumferential direction of the tool bit 120, the second cutting blades 160 extend along the radial direction of the tool bit 120, one side of the second cutting blade 160, which is far away from the tool bit 120, is provided with a second cutting edge, and a plurality of second avoiding grooves are formed in the length direction of the second cutting edge;

the second smoothing blade 170 is disposed on the outer edge of the end face of the tool bit 120, which is far away from one end of the tool holder 110, the second smoothing blade 170 extends along the radial direction of the tool bit and is clamped between two adjacent second cutting blades 160, and a first smoothing edge is disposed on one side of the second smoothing blade 170, which is far away from the tool bit.

The end surface of the tool head 120, which is remote from the end of the tool holder 110, is provided with a plurality of second cutting inserts 160 and first wiper inserts 170, which enable machining in the longitudinal direction of the milling cutter. Of course, the second smoothing blade 170 may be provided in plural, and when provided in plural, the plural second smoothing blades 170 are alternately provided with the plural second cutting blades 160. When the milling cutter is vertically placed, the second cutting blades 160 and the second wiper blades 170 at the end of the cutter head 120 perform cutting work, and the second cutting blades 160 and the second wiper blades 170 at the end of the cutter head 120 are connected to the first cutting blades 130 and the first wiper blades 140 at the outer side walls of the cutter head 120, respectively, to enhance the stability of the cutting blades and the wiper blades at the end of the cutter head 120 and the outer side walls of the cutter head 120. The second cutting blade 160 and the second wiper blade 170 at the end of the cutter head 120 are similar in structure and function to the first cutting blade 130 and the first wiper blade 140 at the outer side wall of the cutter head 120, and thus will not be described in detail.

Optionally, the tool holder 110 is of a cylindrical structure, and the outer diameter is 2mm-10mm

The cutting head 120 is designed to be a column-shaped structure and has a certain length, and the cutting head 120 is connected to one end of the tool shank 110, i.e. the diameter of the cutting head 120 is equal to the outer diameter of the tool shank 110. The first cutting blade 130 is convexly disposed on the outer surface of the tool bit 120 and extends along the length direction of the tool holder 110, so that the first cutting blade 130 is in a long strip shape, the cutting efficiency of the first cutting blade 130 can be improved due to the long strip structure, and at the same time, the contact area between the first cutting blade 130 and the workpiece is increased, that is, the number of workpieces processed at the same time is increased. The outer diameter of the tool shank 110 is limited to 2mm to 10mm, that is, the diameter of the tool tip 120 and the number of the first cutting blades 130 and the first wiper blades 140 provided on the outer surface of the tool tip 120 are defined to ensure the machining accuracy.

Specifically, the cutting head 120 is a cutting member made of an ultrahard composite material.

The tool holder 110 is made of a tungsten carbide (WC) material, and the tool bit 120 is made of a superhard composite material, specifically, polycrystalline diamond (PCD), Polycrystalline Cubic Boron Nitride (PCBN), tungsten carbide, and the like, mainly a combination of PCD and tungsten carbide, and of course, the first cutting blade 130, the first wiper blade 140, the second cutting blade 160, and the second wiper blade 170, which are disposed on the tool bit, are also made of a superhard composite material, so as to increase the cutting strength of the milling cutter. The holder 110 and the tool head 120 are integrally connected by brazing to form a tool usable in a lathe or a boring machine, and the first cutting insert 130, the first wiper insert 140, the second cutting insert 160, and the second wiper insert 170 are formed on the tool head 120 by electric machining.

The above only is the preferred embodiment of the present invention, not limiting the scope of the present invention, all the equivalent structure changes made by the contents of the specification and the drawings under the inventive concept of the present invention, or the direct/indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A milling cutter, comprising:

a knife handle;

the cutter head is arranged at one end of the cutter handle;

the first cutting blades are convexly arranged on the outer side wall of the cutter head, a plurality of first cutting blades are arranged at intervals along the circumferential direction of the cutter head, the first cutting blades extend along the length direction of the milling cutter, a first cutting edge is arranged on one side, away from the cutter head, of each first cutting blade, and a plurality of first avoidance grooves are formed in the length direction of each first cutting edge;

2. The milling cutter according to claim 1, wherein the first wiper blade is provided in plurality, and the plurality of first wiper blades are arranged at intervals in a circumferential direction of the tool bit.

3. The milling cutter according to claim 2, wherein the first wiper blades alternate with the first cutting blades on an outer side wall of the cutter head.

4. The milling cutter according to claim 1, wherein a flute is formed between the first wiper insert and the first cutting insert adjacent thereto, the flute including a first side wall and a second side wall extending in a lengthwise direction of the milling cutter, a spacing between the first side wall and the second side wall gradually increasing in a radially outward direction of the cutter head.

5. The milling cutter according to claim 4, wherein the spacing between the first and second side walls is 0.1mm to 1.0 mm.

6. The milling cutter according to claim 1, wherein the first cutting insert is arranged in a helical configuration in the circumferential direction of the cutter head.

7. The milling cutter tool as claimed in claim 6, wherein the helix angle of the first cutting insert is 45 ° -85 °.

8. The milling cutter tool according to claim 1, wherein the shortest distance between adjacent first cutting inserts is 1.5mm to 5.0 mm.

9. The milling cutter according to claim 1, further comprising:

the second cutting blades are arranged on the outer edge of the end face of one end, far away from the cutter handle, of the cutter head, a plurality of the second cutting blades are arranged at intervals along the circumferential direction of the cutter head, the second cutting blades extend along the radial direction of the cutter head, one side, far away from the cutter head, of each second cutting blade is provided with a second cutting edge, and a plurality of second avoiding grooves are formed in the length direction of each second cutting edge;

10. The milling cutter according to any one of claims 1 to 9, wherein the shank is of cylindrical configuration and has an outer diameter of 2mm to 10 mm;

and/or the tool bit is a cutting piece made of a superhard composite material.