WO2020199974A1

WO2020199974A1 - Milling cutter and ball end mill

Info

Publication number: WO2020199974A1
Application number: PCT/CN2020/080843
Authority: WO
Inventors: 刘东亨
Original assignee: 京瓷株式会社; 刘东亨
Priority date: 2019-03-29
Filing date: 2020-03-24
Publication date: 2020-10-08
Also published as: JP7238159B2; CN113631308A; JP2022528089A; CN111745200B; CN111745200A

Abstract

A milling cutter, having a central cutting edge (101), two main cutting edges (103) respectively extending from two ends of the central cutting edge along the outer periphery of the milling cutter, and two wedge surfaces (111) symmetrically arranged at two sides of the central cutting edge; the central cutting edge (101) is located at the forward-most end of the milling cutter and passes through the rotation center of the milling cutter; the two main cutting edges (103) are connected to the central cutting edge (101) in a smooth transition manner, and the rotation trajectories thereof are on the same hemisphere; a front corner surface (131) and a main chip-removing surface (132) for defining a chip-removing groove are sequentially formed in front of each main cutting edge (103) in the rotation direction; a back corner surface (133) is formed at the rear of each main cutting edge (101) in the rotation direction; an intersecting line of the two wedge surfaces (111) constitutes the central cutting edge (101); one end of each wedge surface (111) is connected to the front corner surface (131) and the main chip-removing surface (132) of one of the main cutting edges, and the other end of the wedge surface (111) is connected to the back corner surface (133) of the other main cutting edge, so that on each side of the central cutting edge, a space that runs through the chip-removing groove (136) of one of the main cutting edges to the back corner surface of the other main cutting edge is formed. The milling cutter can prolong the service life of the milling cutter. Also disclosed is a ball end mill having said milling cutter.

Description

Milling cutter head and ball end mill

Technical field

The invention relates to a cutting tool, in particular to a milling cutter head and a ball end milling cutter.

Background technique

As a kind of cutting tool, the ball end mill is especially suitable for the profiling of the surface of the workpiece.

For example, Chinese invention patent CN104703737B discloses a ball end mill and insert. The cutting edge of the cutter head is in an "S" shape when viewed from the front. The cutting edges on both sides of the rotation center axis of the cutter head intersect the rotation center axis. At the point "P" on the upper side, the "P" point is the end point of the tip (that is, the tip). Wherein, when the cutter head is installed on the cutter handle, the rotation center axis of the cutter head coincides with the rotation center axis of the cutter handle.

During the machining of the ball end mill, the cutter head rotates around its central axis of rotation to process the workpiece. Along the extended length of the cutting edge, the cutting speed at various points of the cutting edge varies with the distance from the central axis of rotation. At the central axis of rotation of the cutter head, the cutting speed of the cutting edge is zero. This usually leads to premature wear and dullness of the cutting edge, chipping or shattering, shortening the tool life.

In the solution provided by the patent CN104703737B, the cutting edges on both sides intersect at point P on the central axis of rotation. During processing, since the cutting speed at the tip of the cutter head is zero, the cutter head and the workpiece slide and scrape at the tip, and the cutting resistance is very large. Therefore, the tip part is prone to premature wear and dullness, chipping or broken, shortening the service life of the tool.

Summary of the invention

An object of the present invention is to provide a milling cutter head to improve the life of the cutter.

Another object of the present invention is to provide a ball end mill with the above-mentioned milling cutter head.

To solve the above technical problems, the present invention adopts the following technical solutions:

According to one aspect of the present invention, the present invention provides a milling cutter head with a center edge located at the foremost end of the milling cutter head and passing through the center of rotation of the milling cutter head; and also having two main cutting edges, Respectively extend from both ends of the central blade along the outer circumference of the milling cutter head; when the two main cutting edges are smoothly connected to the central blade and rotate around the center of rotation, the two main cutting edges and the central blade The rotation trajectory of each main cutting edge is on the same hemisphere; the front of the rotation direction of each main cutting edge is sequentially formed with a rake surface and a main chip removal surface used to define the chip flute; the rotation direction of each main cutting edge is formed behind And two wedge angle surfaces, symmetrically arranged on both sides of the center edge; the intersection line of the two wedge angle surfaces constitutes the center edge; one end of each wedge angle surface is connected to one of the main cuts The rake surface and the main chip removal surface of the blade are in contact with each other, and the other end of the wedge angle surface is in contact with the back angle surface of the other main cutting edge, so that each of the center edges On one side, a space is formed from the chip flute of one of the main cutting edges to the back corner surface of the other main cutting edge.

According to another aspect of the present invention, the present invention also provides a ball end mill, comprising a tool holder and the milling cutter head as described above; the front end of the tool holder is provided with a clamping groove; the milling cutter head is detachably mounted on In the clamping groove.

According to another aspect of the present invention, the present invention also provides a ball end mill, including a tool holder and the above-mentioned milling cutter head integrally formed on the front end of the tool holder.

It can be seen from the above technical solution that the present invention has at least the following advantages and positive effects: In the milling cutter head of the present invention, the two main cutting edges pass through the smooth transition of the center edge, and can contact the workpiece relatively smoothly, reducing cutting impact; more importantly Yes, the center edge is formed on the intersection line of two symmetrically arranged wedge angle surfaces to ensure that the center edge has a certain thickness, so that the center cutting edge has greater strength; further, the center edge is uniform on each side A penetrating chip removal space is formed, and the chips generated at each position can be discharged smoothly, avoiding chip clogging and reducing cutting resistance. Based on the solution of the present invention, the center area of the front end of the milling cutter head has higher strength and a smoother chip removal path, which can effectively reduce the possibility of tool breakage and improve tool life.

Description of the drawings

Fig. 1 is a structural diagram of a ball end mill according to an embodiment of the present invention.

Fig. 2 is a schematic diagram of a three-dimensional structure of a milling cutter head according to an embodiment of the present invention.

Fig. 3 is an end view of Fig. 2.

Fig. 4 is a top view of Fig. 3.

Fig. 5 is a schematic cross-sectional view at C in Fig. 4.

Fig. 6 is a schematic cross-sectional view at M in Fig. 4.

Fig. 7 is a view A-A in Fig. 3.

Fig. 8 is a partial enlarged schematic diagram of D in Fig. 7.

Fig. 9 is an F-F view of Fig. 3.

Fig. 10 is a schematic diagram of the use state of Fig. 2.

Wherein, the illustration of the hatching is omitted in the foregoing FIGS. 5 to 9.

The reference signs are explained as follows: 1. Milling cutter head.

17. The first surface; 18. The second surface; 19. The central hole.

101. The center blade.

111. Wedge angle surface; 112, central chip removal surface; 1121, first chip removal surface; 1122, second chip removal surface; 116, central chip removal groove.

103, the main cutting edge.

131. Front angle surface; 132. Main chip removal surface; 133. Rear angle surface; 1331. Main rear angle surface; 1332. Sub-rear angle surface; 136. Chip removal groove.

2. Tool holder; 21. Tool holder body; 22. Jaw; 24. Clamping groove.

3. Screw.

5. Workpiece.

detailed description

Typical embodiments embodying the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various changes in different implementations, which do not depart from the scope of the present invention, and the descriptions and illustrations therein are essentially for illustrative purposes, rather than limiting this invention.

The invention provides a milling cutter head and a ball end milling cutter with the milling cutter head. Among them, the ball end mill may have a replaceable cutter head structure, or an integrated cutter head and tool holder structure.

Fig. 1 illustrates a ball-end end mill with a replaceable head in an embodiment. The ball end mill includes a tool holder 2 and a milling cutter head 1 detachably mounted on the tool holder 2. The tool holder 2 includes a tool holder main body 21 and two spaced jaws 22 extending from the front end of the tool holder main body 21 (the jaws located above the milling cutter head 1 are removed in the figure). A clamping groove 24 is formed between the handle body 21 and the two jaws 22. The milling cutter head 1 can be fitted in the clamping groove 24, clamped between the two jaws 22, and then fixed to the tool holder 2 by a screw 3.

The tool holder 2 has a roughly cylindrical structure. When the milling tool head 1 is installed in the tool holder 2 for cutting, the tool holder 2 takes the milling tool head 1 to rotate around the central axis of the tool holder 2, and the milling tool head 1 is to be cut The workpiece is processed.

When the milling cutter head 1 needs to be replaced, the screw 3 can be removed, the old milling cutter head 1 is removed, and the new milling cutter head 1 is replaced and tightened again.

In other embodiments not shown in the figure, the ball end mill may also have an integrated structure, and the milling cutter head is integrally formed at the front end of the tool holder.

The structure of the milling cutter head 1 in the ball end mill will be described in detail below in conjunction with the drawings.

Referring to FIGS. 2 to 4, this embodiment is introduced through a replaceable milling cutter head 1.

In this embodiment, the milling cutter head 1 is substantially a flat structure (or a one-piece structure), and the milling cutter head 1 has a first surface 17 and a second surface 18 opposed to each other. The first surface 17 and the second surface The two surfaces 18 are both flat and substantially parallel to each other.

The milling cutter head 1 is provided with a central hole 19 passing through the first surface 17 and the second surface 18. Referring to FIG. 1, when the milling tool head 1 is mounted on the tool holder 2, the first surface 17 and the second surface 18 are in contact with the jaw 22 of the tool holder 2, and the central hole 19 is for the screw 3 to pass through.

When the milling cutter head 1 is working, it rotates around the central axis of rotation L. The arrow in Fig. 2 indicates the direction of rotation. The rotation center axis L is parallel to the first surface 17 and the second surface 18, and is located in the middle position between the first surface 17 and the second surface 18. The rotation center axis L is also connected to the axis of the center hole 19 (not shown in FIG. 2 Show) intersect.

In the direction of the central axis of rotation L, the direction defining the end of the milling cutter head 1 in contact with the workpiece is “front”, and the direction of the end away from the workpiece and close to the tool holder 2 is “rear”.

A central edge 101 and two main cutting edges 103 respectively connected to the two ends of the central edge 101 are formed in the front area of the outer peripheral surface connecting the first surface 17 and the second surface 18. The central edge 101 and the two main cutting edges 103 together constitute the milling The cutting edge of the cutter head 1 is used to process the workpiece. When the milling cutter head 1 rotates around the central axis of rotation L, the rotation trajectories of the cutting edges (that is, including the central edge 101 and the two main cutting edges 103) are on the same hemisphere, so that spherical machining can be performed on the workpiece. With reference to the view direction of FIG. 2, the two main cutting edges 103 are arranged on the left and right sides of the center edge 101 respectively.

The center edge 101 is located at the foremost end of the milling cutter head 1. The center blade 101 is in the shape of a spatial arc, and extends obliquely and monotonously with respect to the first surface 17 and the second surface 18, and has a certain length. The midpoint of the center blade 101 intersects the rotation center axis L, and the center blade 101 is centered symmetric with respect to the rotation center axis L. The two main cutting edges 103 are in a spatial arc shape, are smoothly connected to the central edge 101 and extend along the outer circumference of the milling cutter head 1.

From the end view of the milling cutter head 1 shown in FIG. 3, the combination of the central edge 101 and the two main cutting edges 103 is in an "S" shape. The main cutting edge 103 has a curved shape and extends in a curved shape between the first surface 17 and the second surface 18. The main cutting edge 103 on the right side extends from the end of the central edge 101 toward the first surface 17 first, and then away from the first surface 17 toward the second surface 18. The extended shape of the main cutting edge 103 on the left is just the opposite. The center edge 101 is in a smooth curve shape, and its two ends are smoothly connected to the two main cutting edges 103 respectively. The center edge 101 and the two main cutting edges 103 are combined into an "S" shape, so that the center edge 101 and the main cutting edge 103 can be smoothly and smoothly connected. In the case of interrupted cutting and other processing conditions, the center edge 101 and the main cutting edge 103 The cutting edge 103 can contact the workpiece relatively smoothly, reducing the cutting impact and the probability of tool vibration. In the case of long-term processing, it can effectively reduce the possibility of tool breakage and improve tool life.

From the top view shown in FIG. 4, the front end of the milling cutter head 1 is semicircular. The projections of the central edge 101 and the two main cutting edges 103 fall on the outer contour line of the semicircle. The central edge 101 is located in the central area of the semicircle. The two main cutting edges 103 are arranged on both sides of the central edge 101. . In other words, the projections of the central edge 101 and the two main cutting edges 103 can form a semicircle, which is also a side view of the hemisphere formed by the cutting edge rotation path. As a result, the center edge 101 and the two main cutting edges 103 work together to form a spherical curved surface during cutting. However, it is understandable that, in fact, the end of the main cutting edge 103 away from the central edge 101 is not limited to the end of the semicircle. According to actual conditions, the main cutting edge 103 may further extend backward.

Preferably, the ratio of the extension length b of the central edge 101 (marked in FIG. 3) to the radius R of the semicircle (marked in FIG. 4, which also represents the radius of the hemisphere formed by the cutting edge rotation path) is 1. : 20～1:30, which can better ensure the strength of the milling cutter head 1 and prevent the center edge 101 from cracking.

2, corresponding to the central edge 101 and the two main cutting edges 103, the milling cutter head 1 has at least a wedge angle surface 111 and a central chip removal surface 112 on the outer peripheral surface between the first surface 17 and the second surface 18 , The front corner surface 131, the main chip removal surface 132 and the rear corner surface 133.

Among them, the front corner surface 131, the main chip removal surface 132 and the rear corner surface 133 are arranged corresponding to the main cutting edge 103. The wedge surface 111 and the central chip removal surface 112 are arranged corresponding to the central edge 101.

Taking the view direction of FIG. 2 as a reference, the main cutting edge 103 located on the right side of the center edge 101 is taken as an example for specific description.

2 and 5 together, the main cutting edge 103 and the first surface 17 are connected by a rake surface 131 and a main chip removal surface 132. The rake surface 131 is adjacent to the main cutting edge 103, located in front of the main cutting edge 103 in the direction of rotation, and defines the rake angle of the main cutting edge 103; during cutting, the rake surface 131 directly acts on the cut part of the workpiece and controls Chips are discharged along it, also called the rake face. The main chip removal surface 132 is in contact with the first surface 17. Between the main chip removal surface 132 and the rake surface 131 is formed a chip removal groove 136 for chip removal when the main cutting edge 103 cuts.

In the embodiment shown in FIG. 5, the main cutting edge 103 has a positive rake angle, and the rake angle is preferably between 3° and 8° to ensure sufficient cutting strength and improve the sharpness of the main cutting edge 103. However, in other embodiments, the rake angle of the main cutting edge 103 can also be reasonably designed according to the actual application.

Still referring to FIG. 2 and FIG. 5, the main cutting edge 103 and the second surface 18 are connected by a back corner surface 133. Specifically, in this embodiment, the rear corner surface 133 is divided into a main rear corner surface 1331 and a secondary rear corner surface 1332. The main relief angle surface 1331 is adjacent to the main cutting edge 103, located behind the main cutting edge 103 in the direction of rotation, and defines the relief angle of the main cutting edge 103. The main rear angle surface 1331 and the rake angle surface 131 intersect, and the main cutting edge 103 is provided on the intersection line of the two. During the cutting work, both the main relief angle surface 1331 and the auxiliary relief angle surface 1332 are opposite to the finished surface of the workpiece, and the relief angle surface 133 may also be called the relief surface. The secondary rear corner surface 1332 is in contact with the second surface 18, and the secondary rear corner surface 1332 is more inclined to the second surface 18 relative to the main rear corner surface 1331, thereby forming an avoidance space to ensure that it will not be with the finished surface of the workpiece put one's oar in.

It can be understood that, in some other embodiments, if it is confirmed that it will not interfere with the workpiece, the rear corner surface 133 may also have only the main rear corner surface 1331 without the auxiliary rear corner surface 1332.

Both the extended shape and the extended length of the main cutting edge 103 can be reasonably designed according to actual use occasions, and are not limited here. According to the extended shape of the main cutting edge 103 and the required rake angle and the size of the rear angle, the rake surface 131, the main chip removal surface 132 and the rear angle surface 133 can be adjusted and designed adaptively within a feasible range.

2 and 3, since the two main cutting edges 103 are centrally symmetrical with respect to the central edge 101, for the main cutting edge 103 located on the left side of the central edge 101, it passes through the rear corner surface between it and the first surface 17 133 is connected to the second surface 18 through the front corner surface 131 and the main chip removal surface 132.

Referring to Figures 2, 3 and 7, the upper side of the central edge 101 (wherein, the upper and lower positions are referenced to the view direction of Figure 3) and the first surface 17 pass through the wedge angle surface 111 and the central chip removal surface 112 is connected, and the lower side of the central edge 101 and the second surface 18 are also connected by the wedge surface 111 and the central chip removal surface 112.

The two wedge angle surfaces 111 are centrally symmetrical with respect to the rotation center axis L, and the two wedge angle surfaces 111 intersect, and the intersection line of the two forms the central edge 101. Referring to FIG. 6, when viewed from a section perpendicular to the rotation center axis L, the wedge surface 111 is a smooth curved surface in the extending direction of the center edge 101. In this embodiment, further, the curved surface is a concave curved surface.

For the center edge 101, during cutting, the wedge angle surfaces 111 on both sides can be considered to constitute a rake surface and a flank surface respectively. Referring to Figure 3, with the central axis of rotation L as the boundary, for the right half of the central edge 101, the right half of the wedge surface 111 located above the central edge 101 can be regarded as the rake surface, which is located below the central edge 101 The right half of the wedge surface 111 can be regarded as a relief surface. For the center edge 101 of the left half, the left half of the wedge surface 111 located above the center edge 101 can be regarded as a relief surface, and the left half of the wedge surface 111 located below the center edge 101 can be regarded as Rake face. But because the wedge surface 111 is a smooth curved surface, the chips generated by the right half of the center edge 101 during cutting can actually be discharged along the entire wedge surface 111 on the upper side; similarly, the chips generated by the left half of the center edge 101 It can be discharged along the entire wedge angle surface 111 on the lower side. Therefore, by providing the two wedge angle surfaces 111 and the center edge 101, the chip discharge space at the tip of the cutter head can be effectively enlarged, and the cutting performance of the cutter head can be improved.

As shown in Figures 8 and 9, there is an included angle between the two wedge angle surfaces 111. It should be noted that since the wedge surface 111 is a curved surface in space, the projection of the wedge surface 111 on the cross section perpendicular to the central edge 101 is a curve, and the included angle between the two wedge surfaces 111 refers to: On the cross section of the central edge 101, the angle between the tangents at the intersection of the curves projected by the two wedge angle surfaces 111.

Wherein, the cross section at AA shown in FIG. 8 passes through the central axis of rotation L. At this position, the curves representing the two wedge surfaces 111 are symmetrical, and the angle between the two wedge surfaces 111 at this position is defined as α. The section F-F shown in Fig. 9 deviates from the central axis of rotation L. At this position, the curves representing the two wedge angle surfaces 111 are asymmetrical, and the angle at this position is defined as β. In a preferred embodiment, at any cross section of the central blade 101 (that is, viewed from a cross section perpendicular to the central blade 101), the angle between the two wedge angle surfaces 111 is both 55° to 80°, that is The angles α and β at the two cross-sections mentioned above are both in the range of 55° to 80°. Therefore, a certain thickness can be ensured at the foremost end of the milling cutter head 1, thereby ensuring the strength of the center edge 101, and at the same time, the center edge 101 has a good cutting performance and provides a good tip cutting effect.

In a preferred embodiment, along the extending direction of the central blade 101, the angle between the two wedge angle surfaces 111 exhibits the following change rule: from the middle of the central blade 101 to the two ends, the included angle gradually increases Big. That is to say, at the middle position of the central edge 101, that is, at the position where it intersects the central axis of rotation L, the angle between the two wedge angle surfaces 111 is the smallest; at the end position of the central edge 101, that is, it and the main cutting edge 103 At the position where they meet, the angle between the two wedge angle surfaces 111 is the largest. According to this change rule, the aforementioned included angle β is greater than α. According to this structure, the center of the center edge 101 has a higher sharpness, reduces cutting resistance, and improves the cutting performance of the tip; and the center edge 101 near the two ends has a relatively large thickness, which has higher strength and can The middle position of the center blade 101 plays a role of strengthening and enhances the strength of the center position of the center blade 101.

2 and 3, in the left-to-right direction, one end of the wedge surface 111 is connected with the main back angle surface 1331 of one of the main cutting edges 103, and the other end is connected with the rake surface 131 and main back angle surface 131 of the other main cutting edge 103. The chip removal surfaces 132 are connected. Thereby, a space is formed on both the upper and lower sides of the center edge 101 to penetrate the chip flute 136 of one of the main cutting edges 103 to the rear corner surface 133 of the other main cutting edge 103.

The joint between the wedge surface 111 and the main rear angle surface 1331 is relatively smooth, and there is an obtuse angle between the two, and the joint can be polished to form a smooth transition. There are corners where the wedge surface 111 meets the front corner surface 131 and the main chip removal surface 132, and the corners can also be polished. Compared with the case where the rear corner surface is directly connected to the front corner surface and the main chip removal surface in the prior art, the structure of this embodiment forms a transition through the wedge surface 111. This connection structure is much gentler. The structure of is equivalent to forming an avoidance space in the center edge 101 area, so this design will make it easier to discharge chips, reduce the cutting resistance at the center edge 101, and increase the life of the tool.

Furthermore, the central chip removal surface 112 connected to the wedge angle surface 111 and the first surface 17 (or the second surface 18) also increases the chip removal space of the center edge 101, which is more convenient for chip removal at the center edge 101. The central chip removal surface 112 and the wedge angle surface 111 are smoothly connected.

In this embodiment, on each side of the central edge 101, the central chip removal surface 112 includes a first chip removal surface 1121 and a second chip removal surface 1122 with an included angle, a first chip removal surface 1121 and a second chip removal surface 1122 The surfaces 1122 are all planes and are arranged along the outer circumference of the milling cutter head 1 left and right. The first chip removal surface 1121 is connected with the rear corner surface 133, and the second chip removal surface 1122 is connected with the main chip removal surface 132. The slope of the second chip removal surface 1122 with respect to the rear angle surface 133 is greater than the slope of the first chip removal surface 1121 with respect to the rear angle surface 133. In this way, the chip removal space at the second chip removal surface 1122 is compared with that of the first chip removal surface 1122. The chip evacuation space at the surface 1121 is larger, that is, the chip evacuation space near the chip groove 136 is larger. This structure on the one hand is more compliant with the direction of chip discharge, on the other hand it is more convenient for the smooth transition from the main chip removal surface 132 of one main cutting edge 103 to the rear corner surface 133 of the other main cutting edge 103, and is more It is beneficial to make the front end of the milling cutter head 1 have greater strength.

In other embodiments, the central chip removal surface 112 can also be designed as a larger number of planes connected, wherein, preferably, in the extending direction of the central edge 101, the plane farther from the rear corner surface 133 is opposite to The rear corner surface 133 has a larger slope.

Referring to FIG. 10, when the milling cutter head 1 is working, the central edge 101 and the two main cutting edges 103 contact the workpiece 5 respectively. The milling cutter head 1 rotates around the central axis of rotation L, and processes a flat or spherical curved surface on the workpiece 5 along with the cutting path. Among them, for the center edge 101, according to the cutting method, the wedge surface 111 (refer to Figure 2) on both sides of the center edge 101 can contact the workpiece 5, and the workpiece 5 is processed, and the wedge surface 111 (refer to Figure 2 ). A central chip groove 116 is formed between the central chip surface 112 and the surface of the workpiece 5, and the chips can be discharged smoothly when they reach the central area where the central edge 101 is located. For the chips generated by the cutting of the main cutting edge 103, when the main chip flute 136 (refer to FIG. 5) is too late to be discharged, it can also be discharged through the central chip flute 116, so that the chip evacuation is more smooth.

With reference to Fig. 1, the milling cutter head 1 is installed on the tool holder 2 during operation, and the tool moves along the moving track of the tool holder 2. The rotation center axis L of the milling cutter head 1 coincides with the center axis of the tool holder 2. For the milling cutter head 1 described in the above embodiment, during installation, the first surface 17 and the second surface 18 of the milling cutter head 1 are in contact with the jaws 22 of the shank 2, and the screws 3 fasten the two jaws of the shank 2. The part 22 passes through the central hole 19 of the milling cutter head 1, so that the milling cutter head 1 and the tool holder 2 are fixed.

It can be understood that, based on the different installation methods of the milling cutter head 1, the parallel first surface 17 and the second surface 18 of the milling cutter head 1 described in the above embodiments are not necessary. For example: the first surface 17 and the second surface 18 may not be flat surfaces, and some grooves or protrusions may be provided on one surface for cooperative use; or, the first surface 17 and the second surface 18 may not It must be parallel, it can have a certain angle, etc. For a ball-end end mill with an integrated structure, since it is not necessary to consider the fit with the tool holder, the central hole 19 on the milling cutter head 1 can be removed, and the first surface 17 and the second surface 18 can also be other forms structure.

Although the present invention has been described with reference to a few typical embodiments, it should be understood that the terms used are illustrative and exemplary rather than restrictive. Since the present invention can be implemented in various forms without departing from the spirit or essence of the invention, it should be understood that the above-mentioned embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims. Therefore, all changes and modifications falling within the scope of the claims or their equivalents shall be covered by the appended claims.

Claims

A milling cutter head, characterized in that the milling cutter head has:

A center blade located at the foremost end of the milling cutter head and passing through the center of rotation of the milling cutter head;

Two main cutting edges respectively extend from both ends of the center edge along the outer circumference of the milling cutter head; when the two main cutting edges are smoothly connected to the center edge and rotate around the center of rotation, the two main cutting edges The rotation trajectory of the cutting edge and the center edge is on the same hemisphere; the front of each main cutting edge's rotation direction is sequentially formed with a rake angle surface and a main chip removal surface used to define a chip flute; The rear of the rotation direction forms a rear corner surface; and

Two wedge angle surfaces are arranged symmetrically on both sides of the center edge; the intersection line of the two wedge angle surfaces constitutes the center edge; one end of each wedge angle surface is connected to the front of one of the main cutting edges The corner surface and the main chip removal surface are in contact, and the other end of the wedge corner surface is in contact with the back corner surface of the other main cutting edge, so that each side of the center edge is formed A space that penetrates the chip flute of one of the main cutting edges to the rear corner surface of the other main cutting edge.
The milling cutter head according to claim 1, wherein along the extending direction of the central blade, in the direction from the middle of the central blade to the two ends, the angle between the two wedge angle surfaces gradually Increase.
The milling cutter head according to claim 2, wherein at any cross section of the center edge, the included angle between the two wedge angle surfaces is 55°-80°.
The milling cutter head according to claim 1, wherein, viewed from a section perpendicular to the center of rotation, the wedge surface is a smooth curved surface in the extending direction of the center edge.
The milling cutter head according to claim 4, wherein the curved surface is a concave curved surface.
The milling cutter head according to claim 1, wherein a central chip removal surface is further provided on the side of the wedge angle surface away from the central edge, and the center chip removal surface is between the wedge angle surface A central chip removal groove is formed; one end of the central chip removal surface is connected with the rear corner surface of one of the main cutting edges, and the other end is connected with the main chip removal surface of the other main cutting edge.
The milling cutter head according to claim 6, wherein the central chip removal surface comprises a plurality of planes successively connected along the extending direction of the central edge; in the extending direction along the central edge, the more The plane away from the rear corner surface has a larger slope with respect to the rear corner surface.
The milling cutter head according to any one of claims 1-7, wherein the ratio of the extension length of the central edge to the radius of the hemisphere is 1:20 to 1:30.
The milling cutter head according to any one of claims 1-7, wherein, in an end view of the milling cutter head, the two main cutting edges and the center edge are combined into an S shape.
A ball end mill is characterized in that it comprises:

The tool handle has a clamping groove at its front end;

A milling cutter head is detachably installed in the clamping slot, and the milling cutter head is the milling cutter head according to any one of claims 1-9.
A ball-end end mill, characterized by comprising a tool holder and a milling cutter head integrally formed at the front end of the tool holder, the milling cutter head being the milling cutter head according to any one of claims 1-9.