CN111761111A

CN111761111A - End milling cutter

Info

Publication number: CN111761111A
Application number: CN201910258347.9A
Authority: CN
Inventors: 刘东亨; 朱元锋
Original assignee: Kyocera Corp
Current assignee: Kyocera Corp
Priority date: 2019-04-01
Filing date: 2019-04-01
Publication date: 2020-10-13
Anticipated expiration: 2039-04-01
Also published as: JP7238160B2; JP2022528233A; CN113677467A; CN111761111B; WO2020199975A1

Abstract

The invention provides an end mill. The end mill includes a shank, a blade, and a fastener. The front end of the knife handle is provided with a mounting seat. The mounting seat comprises clamping arms which are oppositely arranged, and a crack is formed between the two clamping arms. The blade is clamped and arranged in the crack. The blade is provided with a through hole and comprises two opposite clamping surfaces. The two clamping surfaces comprise a first clamping surface and a second clamping surface. In a cross section perpendicular to the rotating shaft and including a central axis of the through hole, the first clamping surface includes a first inclined surface and a second inclined surface which are oppositely and obliquely arranged. The inner side surface of the clamping arm is abutted and clamped with the first inclined surface and the second inclined surface, and the clamping arm clamps the blade. The manufacturing difficulty of the end milling cutter is reduced, and the processing yield is improved.

Description

End milling cutter

Technical Field

The present invention relates to an end mill used for cutting.

Background

At present, the fixed installation of the insert of the ball end mill is realized by installing the insert on the installation seat surface of the tool holder through an installation screw or a combination form of the installation screw and the V-shaped constraint surface of the insert. The precision of the center hole of the blade or the precision of the center hole and the precision of the V-shaped surface are ensured to ensure the coaxial mounting precision of the blade and the cutter handle.

Patent document 1: US 20020094244a 1.

Patent document 1 describes a cutting tool in which an arc-shaped surface is provided on a surface of a blade, and an inner side surface adapted to the arc-shaped surface of the blade is provided on a top jaw piece and a bottom jaw piece of a holder, and the purpose of stably holding the blade is achieved by matching the two arc-shaped surfaces. However, in actual production, the processing difficulty of the arc-shaped curved surface is high, and the yield is low.

Disclosure of Invention

The invention aims to solve the problem of increased processing difficulty in the prior art and provide an end mill capable of improving the processing yield.

In order to solve the technical problems, the invention adopts the following technical scheme:

an end mill is a rod extending from front to back along a rotational axis, the end mill comprising a shank, a blade, and a fastener;

the front end of the knife handle is provided with a mounting seat, the mounting seat comprises two oppositely arranged clamping arms, a slit is formed between the two clamping arms, the blade is detachably arranged in the slit, one clamping arm is provided with a mounting hole, and the other clamping arm is provided with a fixing hole;

the blade is clamped and arranged in the crack, rotates around the rotating shaft, a cutting edge for processing is arranged at the front end of the blade, the blade comprises two clamping surfaces opposite to the inner side surfaces of the two clamping arms and through holes formed in the two clamping surfaces, and the fastening piece is connected with the fixing hole by being inserted into the mounting hole and the through holes, so that the blade is detachably arranged on the mounting seat;

the two clamping surfaces comprise a first clamping surface and a second clamping surface;

in a cross section perpendicular to the rotation axis and including the center axis of the through hole, the first clamping surface includes a first inclined surface and a second inclined surface which are arranged obliquely relative to each other, an inner side surface of the clamping arm is abutted and clamped with the first inclined surface and the second inclined surface, and the clamping arm clamps the blade. According to the technical scheme, the invention has at least the following advantages and positive effects:

in the invention, the blade of the end mill is clamped and fixed by the mounting seat, and the surface of the blade comprises two clamping surfaces. The first clamping surface comprises a first inclined surface and a second inclined surface which are oppositely and obliquely arranged. The manufacturing process of the first inclined plane and the second inclined plane is a planar processing process. Correspondingly, the machining operation of the clamping arms is also planar machining, since the inner side surfaces of the clamping arms are complementary to the clamping surfaces. In actual production, the plane processing and monitoring are relatively simple, the operation is easy, and the processing precision is high. Therefore, the processing difficulty of the blade and the clamping arm of the end milling cutter is reduced, and the processing yield is improved.

Drawings

FIG. 1 is a cross-sectional view of an end mill according to an embodiment of the present invention;

FIG. 2 is a perspective view of a mounting block according to the end mill shown in FIG. 1;

FIG. 3 is a cross-sectional view of the mount according to FIG. 2;

FIG. 4 is a perspective view of the blade shown in FIG. 1;

FIG. 5 is a front view of the insert according to FIG. 4;

FIG. 6 is a schematic view of the knife and the gripper arm according to FIG. 4 in a cross section perpendicular to the rotation axis and including the central axis of the through-hole;

FIG. 7 is a schematic view of another embodiment of a blade and clamp arm according to FIG. 6;

FIG. 8 is a schematic view of another embodiment of a blade and clamp arm according to FIG. 6;

FIG. 9 is a cross-sectional view of the blade and fastener shown in FIG. 1;

fig. 10 is a top view of the mount according to fig. 2.

The reference numerals are explained below:

1. a knife handle; 10. a mounting seat;

11. a first clamp arm; 111. mounting holes; 112. a conical support surface;

12. a second clamp arm; 121. a fixing hole; 122. a threaded segment; 123. a smooth section;

13. performing crack filling; 131. a rear sidewall;

2. a blade;

20. a blade;

21. a first clamping surface; 22. a second clamping surface;

211. a first inclined plane; 212. a second inclined plane;

221. a third inclined plane; 222. a fourth slope;

23. a transition surface;

24. a through hole; 241. an inner sidewall;

26. a front end; 27. a back end; 271. a rear end face;

3. a fastener;

31. a head portion; 311. a tapered outer surface;

32. a cylinder; 321. a step portion; 322. an external thread; 323. and (4) smooth surface.

Detailed Description

Exemplary embodiments that embody features and advantages of the invention are described in detail below in the specification. It is to be understood that the invention is capable of other embodiments and that various changes in form and details may be made therein without departing from the scope of the invention and the description and drawings are to be regarded as illustrative in nature and not as restrictive.

The present disclosure provides an end mill. The end mill can be a flat-end mill, a round nose end mill and the like, the type of the end mill is not limited, specifically, the end mill in the application is described by taking a ball end mill as an example, and the rest is not repeated.

Referring to fig. 1, the end mill of the present embodiment is a rod extending from front to back along the rotation axis. The body rotates about its central axis, and the central axis of the body is thus the axis of rotation of the end mill. The end mill is positioned at a front end of the end mill, and the other end of the end mill in the direction of the rotation axis is a rear end of the end mill with respect to the front end.

The end mill comprises a shank 1, an insert 2 and a fastener 3. The blade 2 is detachably fixed to the handle 1 by a fastener 3.

The fastener 3 includes a head 31 and a shank 32. In particular, the fastener 3 is a screw that is adapted to the mounting seat 10 and the insert 2. The column 32 is a screw column, and the head 31 is a screw head. It is understood that the fastening member 3 may be a screw rod, a nut, or a combination thereof, besides a screw.

The knife handle 1 is a cylinder. The shank 1 is attached to a spindle of a machine tool, and the end mill can be driven to rotate in the axial direction of the shank 1, and the rotating end mill can machine a workpiece such as metal. The axial direction of the tool holder 1 is the direction of the rotating shaft. The one end that handle of a knife 1 is close to the processing position along the rotation axis direction is the front end of handle of a knife, and is relative, and the other end of handle of a knife is the rear end of handle of a knife.

Specifically, in the present embodiment, the mount 10 is located at the front end of the shank 1. The mounting seat 10 is a part of the tool shank 1, and the mounting seat 10 and the tool shank 1 are of an integral structure. The front end of the tool shank 1 is cut into the mounting seat 10 by a cutting process. The mounting seat 10 is used for mounting the blade 2.

The blade 2 is a plate-shaped blade. One end of the blade 2 near the machining position in the rotation axis direction is a front end 26 of the blade 2, the cutting edge 20 of the blade 2 is provided at the front end 26, and the other end of the blade 2 is a rear end 27 of the blade 2. The direction from the front end 26 to the rear end 27 is the front-rear direction of the blade 2. The front and back directions of the blade 2 along the direction of the rotating shaft of the blade 2 are the axial directions of the blade 2, and the directions perpendicular to the axial direction and parallel to the plane of the blade 2 are the radial directions of the blade 2. As shown in fig. 2, for convenience of explanation, the rotation axis direction of the blade 2 is defined as an X-axis direction, the radial direction of the blade 2 is defined as a Y-axis direction, and the direction perpendicular to the X-axis and the Y-axis is defined as a Z-axis direction.

Referring to fig. 2 and 3, the mounting base 10 includes two clamping arms disposed opposite to each other. The two clamping arms are respectively a first clamping arm 11 and a second clamping arm 12. The first clamping arm 11 and the second clamping arm 12 are arranged oppositely.

A slit 13 is formed between the first clip arm 11 and the second clip arm 12. The slit 13 is used to clamp the fixed blade 2. The shape of the nip 13 matches the shape of the blade 2. The shapes of the first clamping arm 11 and the second clamping arm 12 are complementary to the shape of the blade 2, so that the first clamping arm 11 and the second clamping arm 12 can be tightly attached to the blade 2. Moreover, the shapes and sizes of the first clamping arm 11 and the second clamping arm 12 are also matched with the shape and size of the blade 2, so that the inner side surface of the first clamping arm 11 and the inner side surface of the second clamping arm 12 can be completely contacted with the outer side surface of the blade 2 to bear force, and the blade 2 is stably fixed in the gap 13.

The first clamping arm 11 and the second clamping arm 12 are both provided with an inner side surface and an outer side surface. The inner side surface of the first clamping arm 11 and the inner side surface of the second clamping arm 12 are both located in the slit 13 and are two inner side surfaces which are arranged oppositely. The outer side surface of the first clip arm 11 and the outer side surface of the second clip arm 12 are located on opposite sides of the two inner side surfaces.

The blade 2 is fixed by a mount 10 and rotates about a rotation axis L. The blade 2 is clamped in the nip 13.

The insert 2 comprises two oppositely arranged clamping surfaces. Referring to fig. 1 and fig. 4, the two clamping surfaces include a first clamping surface 21 and a second clamping surface 22. The first clamping surface 21 and the inner side surface of the first clamping arm 11 are abutted against each other. The second clamping surface 22 and the inner side surface of the second clamping arm 12 abut against each other.

The first clamping surface 21 comprises two inclined surfaces inclined to the central axis of the through hole 24. The two inclined surfaces disposed on the first clamping surface 21 are a first inclined surface 211 and a second inclined surface 212, respectively. The first inclined surface 211 is disposed to be inclined with respect to the second inclined surface 212.

In other embodiments, the positions of the first clamping surface 21 and the second clamping surface 22 may be interchanged. The first clamping surface 21 and the second clamping arm 12 are abutted against each other. The specific positions of the first clamping surface 21 and the second clamping surface 22 are not limited herein.

The first and

second clamp arms

11 and 12 clamp the insert 2, and provide the insert 2 with a restraining force perpendicular to the rotation axis L and to both clamping surfaces of the insert 2. The restraining force is resolved in the Z-axis direction and the Y-axis direction. First, the first and

second clamp arms

11 and 12 provide a clamping force to the blade 2 along the Z-axis direction to ensure that the blade 2 is kept stable in the Z-axis direction. In addition, since the first inclined surface 211 and the second inclined surface 212 are obliquely arranged, the first clamping arm 11 provides a first radial restraining force to the blade 2 in the radial direction, and the first radial restraining force is in the Y-axis direction. The first radial restraining force may ensure that the insert 2 remains stable in the radial direction.

In addition, the first clip arm 11 is provided with a mounting hole 111, and the second clip arm 12 is provided with a fixing hole 121. The blade 2 is provided with a through hole 24. When the blade 2 is held between the first arm 11 and the second arm 12, the mounting hole 111, the through hole 24, and the fixing hole 121 are disposed to face each other. Wherein, the mounting hole 111 is a smooth hole. The fixing hole 121 is a screw hole. The through hole 24 is a smooth shaft hole. The fastening member 3 is screwed to the second arm 12 through the mounting hole 111 of the first arm 11 and the through hole 24 of the blade, and detachably fixes the blade 2 to the mounting seat 10.

In the end mill, the first clamping surface 21 includes the first inclined surface 211 and the second inclined surface 212 which are provided obliquely. The first inclined surface 211 and the second inclined surface 212 are both flat surfaces. The manufacturing process for the first clamping surface 21 is a planar machining process. Accordingly, the machining operation for the first clamping arm 11 is also planar, since the inner side of the first clamping arm 11 is complementary to the first clamping surface 21. In actual production, the plane processing and monitoring are relatively simple, the operation is easy, and the processing precision is high. Therefore, the processing difficulty of the end milling cutter in the processing process is reduced, and the processing yield is improved.

Referring to fig. 6, in the present embodiment, in a cross section perpendicular to the rotation axis L and including the central axis of the through hole 24, the first inclined surface 211 and the second inclined surface 212 are respectively disposed on both sides of the central axis of the through hole 24.

It is understood that, as shown in fig. 7, in other embodiments, the first inclined surface 211 and the second inclined surface 212 are not necessarily provided on both sides of the central axis of the through hole 24. In a cross section perpendicular to the rotation axis L and including the center axis of the through hole 24, the length of the first inclined surface 211 is longer than the length of the second inclined surface 212, and thus the object of reducing the difficulty of machining the end mill can be achieved, and the machining yield can be improved.

Referring to fig. 6, in the present embodiment, in a cross section perpendicular to the rotation axis and including the central axis of the through hole, the first inclined surface 121 and the second inclined surface 122 are closer to the second clamping surface 22 as they are farther from the through hole 24. The first inclined surface 211 and the second inclined surface 212 are both flat surfaces.

In a cross section perpendicular to the rotation axis and including the center axis of the through hole, the thickness of the blade 2 gradually decreases as it goes away from the through hole 24. The thickness of the blade 2 is the width of the blade 2 in the direction along the center axis of the through hole 24. That is, as shown in fig. 6, in a cross section perpendicular to the rotation axis and including the center axis of the through hole, the center portion of the insert 2 is thick and both the left and right sides are thin in the radial direction of the insert 2. The first inclined surface 211 and the second inclined surface 212 are arranged in an arch shape. Correspondingly, the middle part of the first clamping arm is concave. The insert 2 has a large thickness and a high strength at the rotation axis L, and the overall rigidity of the end mill can be improved.

The first inclined surface 121 and the second inclined surface 122 may intersect with each other, or another connecting surface (not shown) may be disposed between the first inclined surface 121 and the second inclined surface 122. It is sufficient to ensure that the first inclined surface 121 and the second inclined surface 122 can get closer to the second clamping surface 22 as they get farther from the through hole 24.

Specifically, in the present embodiment, in a cross section perpendicular to the rotation axis L and including the central axis of the through hole 24, the first inclined surface 211 and the second inclined surface 212 intersect at the central axis of the through hole 24. The connecting surface may not be provided between the first inclined surface 121 and the second inclined surface 122, so that the areas of the first inclined surface 211 and the second inclined surface 212 are as large as possible, the contact area between the blade 2 and the first clamping arm 11 can be increased, and the blade 2 can be stably constrained on the mounting seat 10.

In another embodiment, in a cross section perpendicular to the rotation axis and including the center axis of the through hole, the first inclined surface 121 and the second inclined surface 122 are farther from the second clamping surface 22 as they are farther from the through hole 24. The thickness of the blade 2 may be gradually reduced from both sides of the blade 2 toward the direction of the rotation axis L of the blade 2. That is, in a cross section perpendicular to the rotation axis and including the center axis of the through hole, the middle portion of the blade 2 may be thin, and the first inclined surface 121 and the second inclined surface 122 may be recessed. Two inclined planes which are used for being abutted against the support arm can be provided, so that the processing difficulty of the end mill is reduced, and the processing yield is improved.

Specifically, in the present embodiment, in a cross section perpendicular to the rotation axis and including the center axis of the through hole, the first inclined surface 211 and the second inclined surface 212 intersect at the center axis of the through hole 24 of the insert, and are disposed in an inverted V shape. The planar contact area between the first inclined surface 211 and the first clamping arm 11 and the planar contact area between the second inclined surface 212 and the first clamping arm 11 are as large as possible, so that the constraint of the blade 2 is more stable.

As shown in fig. 5, the included angle between the first inclined surface 121 and the second inclined surface 122 is a, and the angle a is 120 to 170 degrees. That is, the included angle between the first inclined surface 211 and the second inclined surface 212 is 120 degrees to 170 degrees, so that the restraining force can be better dispersed in the Y-axis direction and the Z-axis direction, and the stability of the blade in the Y-axis direction and the Z-axis direction can be ensured.

Specifically, in the present embodiment, the included angle between the first inclined surface 211 and the second inclined surface 212 is 160 degrees, and in other embodiments, the included angle between the first inclined surface 211 and the second inclined surface 212 may be any angle within a range of 120 degrees to 170 degrees.

The first inclined surface 211 and the second inclined surface 212 are provided symmetrically with respect to a plane on which the rotation axis L and the center axis of the through hole 24 are located. The first inclined surface 211 and the second inclined surface 212 are symmetrically arranged about the plane where the rotation axis L and the center axis of the through hole 24 are located, so that the constraint force exerted on the first inclined surface 211 and the second inclined surface 212 can be kept symmetrical, the symmetrical radial constraint force exerted on the blade 2 can be guaranteed, and the blade 2 can be kept balanced better.

Referring to fig. 5 and 6, the second clamping surface 22 includes two inclined surfaces inclined to the central axis of the through hole 24. The two inclined surfaces provided on the second clamping surface 22 are respectively a third inclined surface 221 and a fourth inclined surface 222. The inner side surface of the second clip arm 12 abuts against and clamps the third inclined surface 221 and the fourth inclined surface 222. The third inclined surface 221 and the fourth inclined surface 222 are both flat surfaces. The second clamping arm 12 provides a second radial restraining force to the second clamping surface 22 of the blade 2 in the radial direction, since the third and fourth

inclined surfaces

221 and 222 of the second clamping arm 12 are inclined, and the second radial restraining force is in the Y-axis direction. The second radial restraining force may ensure that the insert 2 remains stable in the radial direction.

Specifically, in the present embodiment, the first clamp surface 21 and the second clamp surface 22 are symmetrically disposed with respect to a plane perpendicular to the center axis of the through hole 24 and passing through the center of the center axis.

Specifically, as shown in fig. 5, the first clamping surface 21 and the second clamping surface 22 are disposed symmetrically up and down with respect to the insert 2. The first clamping surface 21 and the second clamping surface 22 are arranged symmetrically up and down with respect to the central axis plane B of the insert 2. The central axis plane B of the blade 2 is a plane passing through the rotation axis L, perpendicular to the central axis, and passing through the center of the central axis. The first clamping surface 21 and the second clamping surface 22 are arranged vertically symmetrically, so that the upper and lower stress of the blade 2 can be ensured to be symmetrical, and the blade 2 is not easy to deviate due to uneven stress.

The size of the included angle between the first inclined surface 211 and the second inclined surface 212 is equal to the size of the included angle between the third inclined surface 221 and the fourth inclined surface 222. As shown in fig. 5, the included angle between the first inclined surface 211 and the second inclined surface 212 is 120 to 170 degrees. Then, the included angle between the third inclined surface 221 and the fourth inclined surface 222 is also 120 degrees to 170 degrees. The inclination angles of the third inclined surface 221 and the fourth inclined surface 222 can better disperse the restraining force in the Y-axis direction and the Z-axis direction, and ensure the stability of the blade 2 in the Y-axis direction and the Z-axis direction.

Specifically, in the present embodiment, the included angle between the third inclined surface 221 and the fourth inclined surface 222 is 160 degrees. In other embodiments, the included angle between the third inclined surface 221 and the fourth inclined surface 222 may be any angle within a range of 120 degrees to 170 degrees. As long as the included angle between the third inclined surface 221 and the fourth inclined surface 222 is equal to the included angle between the first inclined surface 211 and the second inclined surface 212.

And the first clamping surface 21 and the second clamping surface 22 have the same distance distribution with respect to the median axis plane B of the insert. Thus, the forces on the first clamping surface 21 and the second clamping surface 22 are symmetrical, so that the insert is kept in force balance. The distances from the 4 inclined surfaces of the first clamp surface 21 and the second clamp surface 22 to the rotation axis L are equal. 4 inclined planes which are symmetrically arranged can ensure that the end mill has higher coaxiality.

In other embodiments, the angle between the first inclined surface 211 and the second inclined surface 212 may not be equal to the angle between the third inclined surface 221 and the fourth inclined surface 222.

In another embodiment, as shown in fig. 7, the first clamping surface 21 and the second clamping surface 22 are arranged in a central symmetry with respect to a plane perpendicular to the central axis of the through hole 24 and passing through the center of the central axis. The first clamping arm 11 generates a centrosymmetric constraint force on the first inclined surface 211 and the second inclined surface 212, and the second clamping arm 12 generates a centrosymmetric constraint force on the third inclined surface 221 and the fourth inclined surface 222. And the blade 2 can be stressed symmetrically up and down, and the blade 2 can be stably fixed.

In other embodiments, as shown in fig. 8, the second clamping surface 22 may be a plane, and the second clamping surface 22 is in plane contact with the second clamping arm 12, so that the second clamping arm 12 can also generate a clamping force on the second clamping surface 22 of the blade 2 along the Z-axis direction.

As shown in fig. 1, the blade 2 is accommodated in the slit 13, and the rear end 27 of the blade 2 is provided with a rear end surface 271 for abutting against the mount base 10. The rear end face 271 of the blade 2 abuts against the rear side wall 131 of the slit 13. Therefore, the rear side wall 131 of the mount 10 and the rear end surface 271 of the insert 2 abut against each other, and the mount 10 supports the insert 2 from the rear end of the insert 2. The rear end surface 271 is a flat surface. The mounting seat 10 can be stably contacted with the blade 2 through the rear end surface 271, so as to ensure that the blade 2 can be stably supported. The blade 2 is detachably mounted to the mounting block 10 by means of fasteners 3. Fastener 3 is connected to mount 10 through blade 2. It will be appreciated that the fastener 3 is a screw that mates with the mounting block 10 and the insert 2.

Specifically, in the present embodiment, referring to fig. 1, the fastener 3 includes a head 31 and a shank 32. The column 32 is a screw column, and the head 31 is a screw head.

Referring to fig. 9, in the present embodiment, the mounting hole 111 is used for receiving the head 31 of the fastener 3. The outer side surface of the head 31 is engaged with and abutted against the inner side surface of the mounting hole 111. The mounting hole 111 is a tapered counterbore. The inner side wall of the mounting hole 111 is a conical support surface 112. Correspondingly, the head 31 of the fastener 3 is tapered, the head 31 having a tapered outer surface 311. The tapered bearing surface 112 is in cooperative abutment with the tapered outer surface 311.

In other embodiments, the mounting hole 111 need not be a counterbore, and the head 31 of the fastener 3 need not be received in the mounting hole 311. It is only necessary that the fastener 3 can pass through the first clip arm 11 and the head 31 abuts against the outer side surface of the first clip arm 11. Moreover, the mounting hole 111 may be a counterbore with other shapes as long as the inner sidewall of the mounting hole 111 can provide a supporting surface for supporting.

Referring to fig. 10, the tapered supporting surface 112 and the fixing hole 121 are eccentrically disposed. And the center of the tapered support surface 112 is disposed toward the rear end. The proximal front end side of the head 31 abuts against the tapered support surface 112 portion proximal to the front end. When the fastening member 3 is attached, the fastening member 3 is forced, the forward side of the head 31 and the forward side of the attachment hole 111 abut against each other, and the tapered support surface 112 can support the head 31 of the fastening member 3, thereby generating a clamping force in the central axis direction of the through hole 24. The clamping force is in the Z-axis direction.

Referring to fig. 1, in the present embodiment, the fixing hole 121 is divided into a threaded section 122 and a smooth section 123 along the axial direction. The smooth section 123 is located on the side adjacent to the blade 2 and the threaded section 122 is threadedly connected to the post 32. The smooth section 123 is not threaded as a shaft hole. The fixing hole 121 is used for the column 32 of the fastener 3 to be connected. Accordingly, the end of the cylinder 32 remote from the head 31 is provided with an external thread 322, and the rest of the cylinder 32 is a smooth surface 323. The cylinder 32 is screwed into the fixing hole 121 through the external thread 322.

Before the cylinder 32 is threaded into the threaded section 122 for threaded connection, the cylinder 32 can be positioned through the axial hole of the smooth section 123, and after the threaded section 122 is positioned, the cylinder 32 can be rotated to thread and fasten the cylinder 32 to the mounting seat 10. The threaded section 122 of the second clamping arm 12 is in threaded connection with the external thread 322 of the column 32, and the smooth surface 323 of the remaining column 32 is matched with the smooth section 123 of the fixing hole 121, so that the position accuracy of the fastener 3 can be conveniently controlled.

Referring to fig. 9, the central axis of the mounting hole 111 and the central axis of the fixing hole 121 are offset, and the central axis of the fastening member 3 and the central axis of the through hole 24 are offset. Therefore, the fastener 3 is displaced during the tightening process by pressing, and the smooth surface 323 of the column 32 in the through hole 24 is in surface contact with the inner side wall 241 of the through hole 24, so as to generate an axial restraining force along the direction of the rotation axis L. Therefore, the requirement for the processing accuracy of the through hole 24 is not high, and the manufacturing difficulty is reduced.

Further, since the insert 2 receives an axial reaction force during the cutting process of the end mill, the rear end surface 271 of the insert 2 is supported by the rear side surface 131 of the mount base, and the mount base 10 can receive most of the axial reaction force. Since the mount 10 is able to counteract most of the axial reaction, the remaining axial reaction forces can be counteracted by the axial restraining force. Therefore, the fastener 3 is subjected to only a small axial reaction force, which can reduce wear on the fastener 3 and increase the life of the fastener 3.

Because the blade and the clamping arm are contacted through the cambered surface in the scheme of the traditional end milling cutter, firstly, the machining difficulty angle of the cambered surface is difficult to monitor; moreover, the curvature radius of the cambered surface of the blade is smaller than that of the cambered surface of the clamping arm, and the contact between the blade and the two cambered surfaces of the clamping arm can only be 3 or 4 line contacts. Therefore, the contact area between the blade and the clamping arm is small, the blade cannot be stably restrained and fixed, and the blade is easy to deflect.

Compared with the traditional end mill, the contact constraint between the blade 2 and the clamping arm is realized by 4 inclined surfaces, namely a first inclined surface 211, a second inclined surface 212, a third inclined surface 221 and a fourth inclined surface 222. At least 3 inclined surfaces can be kept in contact with the blade 2 at the same time, so that good restraining force can be provided, and the blade 2 can be prevented from deflecting.

Even under the condition that machining deviation exists, the blade 2 of the application is in contact with the clamping arm through at least one inclined surface, and the other 3 inclined surfaces are in line contact with the clamping arm through at least one line. Therefore, the restriction area between the insert 2 and the clamp arm of the end mill of the present embodiment is large, ensuring more stable restriction.

In addition, since the distance between the 4 inclined surfaces of the first clamping surface 21 and the second clamping surface 22 and the rotation axis L directly affects the coaxiality of the insert 2, the distance between the inclined surfaces and the rotation axis L is easier to control, and the accuracy is easier to ensure. Therefore, the end mill can have high coaxiality.

While the present invention has been described with reference to several exemplary embodiments, it is understood that the terminology used is intended to be in the nature of words of description and illustration, rather than of limitation. As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.

Claims

1. An end mill is a bar extending from front to back along a rotational axis, wherein the end mill comprises a shank, a blade, and a fastener;

in a cross section perpendicular to the rotation axis and including the center axis of the through hole, the first clamping surface includes a first inclined surface and a second inclined surface which are arranged obliquely relative to each other, an inner side surface of the clamping arm is abutted and clamped with the first inclined surface and the second inclined surface, and the clamping arm clamps the blade.

2. The end mill according to claim 1, wherein the first inclined surface and the second inclined surface are provided on both sides of a central axis of the through hole in a cross section perpendicular to the rotation axis and including the central axis of the through hole.

3. The end mill according to claim 1, wherein, in a cross section perpendicular to the rotation axis and including a center axis of the through hole, the first and second inclined surfaces are closer to the second clamping surface as being farther from the through hole.

4. The end mill according to claim 1, wherein, in a cross section perpendicular to the rotation axis and including a central axis of the through hole, a thickness of the insert gradually becomes smaller as being farther from the central axis of the through hole.

5. The end mill according to claim 1, wherein, in a cross section perpendicular to the rotation axis and including a central axis of the through hole, the first and second slopes intersect at the central axis of the through hole.

6. The end mill according to claim 1, wherein the first and second bevels are planar.

7. The end mill according to claim 1, wherein the angle between the first and second inclined surfaces is 120-170 degrees.

8. The end mill according to claim 1, wherein the first inclined surface and the second inclined surface are provided symmetrically with respect to a plane in which the rotation axis and a center axis of the through hole are located.

9. The end mill according to claim 1, wherein the second clamping surface includes a third inclined surface and a fourth inclined surface inclined with respect to a central axis of the through hole, and the inner side surfaces of the clamping arms are clamped in abutment with the third inclined surface and the fourth inclined surface.

10. The end mill according to claim 1, characterized in that the first clamping surface and the second clamping surface are symmetrically arranged with reference to a plane perpendicular to the central axis and passing through the center of the central axis.

11. The end mill according to claim 1, wherein a central axis of the through hole is provided eccentrically from a central axis of the fixing hole.

12. The end mill according to claim 1, wherein the fastener includes a post and a head, the post penetrates the through hole from the mounting hole, the fixing hole is connected to the mounting seat, the head abuts an outer side surface of a clip arm in which the mounting hole is opened, and one side of the post abuts an inner side wall of the through hole.

13. The end mill according to claim 12, wherein the mounting hole is a tapered counterbore, the inner side wall of the mounting hole is a tapered bearing surface, and the head portion includes a tapered outer surface against which the tapered bearing surface interfits.

14. The end mill according to claim 1, wherein the fixing hole is divided in its axial direction into a threaded section and a smooth section, the smooth section being located on a side of the fixing hole close to the insert, the threaded section being threadedly connected with the fastener.

15. The end mill according to claim 1, wherein a rear end face of the insert abuts a rear side wall of the slot.

16. The end mill according to claim 15, wherein the rear end face of the insert is planar.