JPH10118824A - Vertical type tip and milling cutter therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use as many corners as possible. SOLUTION: A vertical type tip 10 is a flat plate type tip a front surface shape of which is generally square and its side surface 12 is shaped depressed inside. Consequently, an angle made by the side surfaces 12 adjacent to each other becomes acute, and a part of the side surface 12 in the neighbourhood of each of the angles becomes a rake face 50. By making this shape, it is possible to form totally eight sets of cutting blades 30, flanks 40, the rake faces 50, etc., on the four side surfaces 12 of the vertical type tip 10, and it becomes possible to use eight corners. Additionally, it is possible to provide a milling cutter 60 capable of extending longevity of the vertical type tip 10 as a whole by making a tip installation seat 64 of a body 62 in a shape free to install the tips represented by the vertical type tip 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical insert removably attached to a cutting tool, and a milling cutter provided with the vertical insert.

[0002]

2. Description of the Related Art Vertical inserts removably attached to the body of a cutting tool are already known. In the vertical chip, any one of the side surfaces is a rake surface in a use state. A through hole is formed at the center of the flat chip, and the mounting hole is used to attach to the tool body with a fixing member such as a bolt. The workpiece and a direction substantially perpendicular to the center line of the mounting hole. The intersection of two adjacent side surfaces among the plurality of side surfaces of the flat chip functions as a cutting edge, one of the two side surfaces functions as a rake surface, and the other functions as a flank surface. It will be.

[0003] Taking vertical inserts of a milling cutter for roughing as an example, conventionally, one to six corners of each chip have been actually used for cutting, and these are 1 to 6 corners. It is called an errand. It is necessary to satisfy the requirement that the shape (referred to as a blade shape) of the blade shape (the profile of the blade portion having a cross section perpendicular or parallel to the axis) be a so-called negative-positive type (NP type) or a double positive type (DP type). It is inevitable when there is. The NP type and DP type blade shapes will be described in embodiments of the present invention. In order to realize such a blade-shaped shape, it is necessary that the tip has a shape including one to three acute angles in a frontal shape. For example, in the case of a vertical chip having a frontal shape of an equilateral triangle, three corners can be used in two corners on the front and back, respectively, so that a chip having six corners can be used.

[0004]

In the above-mentioned conventional vertical chip, the front shape is outwardly convex.
Therefore, of the angles included in the cross-sectional shape, only one to three can be made acute. Therefore, in order to satisfy the demand for a so-called negative-positive type (NP type) or double positive type (DP type),
The number of rake faces is limited to two to six. Since one rake surface can be used for each rake face, as described above, two to six corners are used.
However, in general, the ratio of the portion that actually contributes to cutting to the size of the volume (or surface area) of the chip body in which relatively expensive materials are used is generally small, and in order to increase this ratio, It is desirable to have as many corners as possible.

[0005] Therefore, an object of the first invention according to claim 1 of the present application is to obtain a vertical die that can be cut at as many corners as possible. The problems of the second invention according to claim 2 and the third invention according to claim 3 are as follows.
It is an object of the present invention to increase the number of usable corners of the vertical chip as much as possible without sacrificing usability. A fourth object of the present invention is to effectively utilize the vertical insert of the first to third aspects for milling.

[0006]

Means for Solving the Problems, Functions and Effects of the Invention
In the first invention, the above-mentioned problem is that the front shape is a square, and that each side of the square of the flat chip having a mounting hole formed in the center portion is recessed inward, so that The angle between adjacent sides is made acute,
The problem is solved by making each of the side faces usable as a rake face. With such a shape, the blade shape is changed to the negative-positive type (NP type).
Alternatively, a double positive type (DP type) can be used, and the front shape can be a shape including four acute angles. The present chip is particularly suitable as a chip for milling, but can also be used as a chip for other uses such as a cutting tool.

[0007] In the second invention, the above object is achieved by the vertical chip according to the first invention, wherein each side of the square is a bent line bent at a midpoint, and the mounting hole is symmetrical with respect to the center in the axial direction. It is solved by adopting a simple shape. Each side of the square, which is the basic shape, can be a polygonal line bent at a point other than the middle point, but in this case, the shape changes if the chip is turned upside down. Therefore, in order to use the 8 corners under the same conditions (the same rake angle and clearance angle) by turning over,
It is necessary to prepare two types of tip mounting seats for the tool body, one for the front and the other for the back, which makes the usability of the tip worse. On the other hand, a chip with a polygonal line bent at the midpoint on each side of the square, which is the basic shape, has no change in shape even if it is turned upside down, so if the mounting hole is symmetrical with respect to the center in the axial direction, The insert can be mounted on the insert mounting seat of the same shape on the tool body with the front and back turned over, so that a total of 8 corners, 4 corners on the front and 4 corners on the back, can be easily used.

[0008] In the third invention, the object is to provide a vertical chip according to the first invention, wherein each side of the square is
At least the central portion is smoothly curved, a concave curve having a shape symmetrical with respect to the middle point, and the mounting hole is formed with a shape symmetrical with respect to the center in the axial direction. Also in this case, if the concave curve has a symmetrical shape with respect to the middle point and the mounting hole has a symmetrical shape with respect to the center in the axial direction, eight corners can be easily used on both sides. In addition, the vertical tip of the first to third inventions has a vertical basic shape of a square shape, but a vertical pentagon or a regular polygon having more than five cutting edges as a regular polygon. It is also possible to form. However, if such a vertical insert has a symmetrical shape, the edge angle becomes very sharp and the strength is significantly reduced.
The scope of application is limited.

[0009] In the fourth invention, the above object is achieved by allowing the vertical chip according to any of the first to third inventions to be seated on a chip mounting seat formed at a plurality of tip portions of the outer peripheral surface of the body. The problem is solved by using a milling machine fixed by bolts inserted into the mounting holes. For example, when the material to be cut is steel and rough cutting is performed by a face mill, the life of the chip decreases as the processing speed increases. In such a case, the use of the vertical chip according to the first to third aspects of the present invention makes it possible to double the life at a stroke as compared with the conventional four-corner vertical chip that has been generally used. Can be.

[0010]

Supplementary Description of the Invention The present invention can be carried out in the following embodiments in addition to the embodiments described in the above claims. Each embodiment is conveniently described as an embodiment of the same type as the claims. (1) The vertical tip according to any one of claims 1 to 3, wherein a portion forming the cutting edge is formed of a material having higher hardness than other portions. (2) An embodiment in which a chip body and a high-hardness piece having a higher hardness than the chip body are provided, and the high-hardness piece is brazed to mounting seats formed in parallel with each side surface from four corners of the chip body. Item 4. A vertical chip according to Item 1. The vertical insert according to the first or second embodiment can easily manufacture a blade portion made of a material suitable for cutting conditions such as a material to be cut and a processing speed, as described in the embodiments of the invention later. Things. (3) The mounting hole is formed closer to the surface than the center position in the thickness direction of the vertical die, and the first tapered portion whose diameter increases toward the surface, and symmetrically with the first tapered portion. The vertical chip according to any one of claims 2 and 3, further comprising a second tapered portion formed on the back surface side. If the mounting hole has such a cross-sectional shape and the mounting bolt has a tapered portion, it is possible to mount the front and rear surfaces stably and with high positioning accuracy. (4) The vertical tip according to any one of the first to third embodiments is seated on a tip mounting seat formed at the tip of the cutting tool body, and is inserted through the mounting hole. A tool fixed with bolts.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A vertical chip according to one embodiment of the first invention and the second invention of the present application will be described with reference to the drawings. FIG. 1 is a front view of the vertical chip 10 and FIG. 2 is a right side view thereof. The vertical tip 10 is a milling throw-away tip integrally formed by sintering a cemented carbide. Its front shape is generally square, and as shown in FIG. 1, the four side surfaces 12 are concavely shaped to form an acute angle (70 degrees) at four corners. As shown in FIG. 2, a mounting hole 18 is provided at the center of the front surface 14 having a substantially square shape and the back surface 16 opposed thereto. The mounting hole 18 has a first tapered portion 20 (see FIG. 1) whose diameter increases toward the front surface 14, and a second tapered portion 22 formed on the back surface 16 side symmetrically with the first tapered portion 20. (See FIG. 2). The vertical die 10 is rotationally symmetrical twice with respect to any one of the two center lines (dashed lines) shown in FIG. In addition, it is symmetrical four times with the center line of the mounting hole 18 as a rotation axis. Therefore, the front surface 14 and the back surface 1
6, the first tapered portion 20 and the second tapered portion 22
Are substantially the same. The four side surfaces 12 also have the same shape.

As shown in FIG. 2, cutting edges 30 are formed at two diagonal positions of the side surface 12. The cutting edge 30 includes a main cutting edge 32, a first sub cutting edge 34, and a second sub cutting edge 36. The main cutting edge 32 is formed by forming the flank 40 at two positions on the side surface 12 at diagonals different from the position where the cutting edge 30 is formed. The flank 40 includes a main flank 42, a first sub flank 44, and a second sub flank 46. The main cutting edge 32 and the first sub cutting edge 34 are formed by forming a main flank 42 and a first sub flank 44 on a part of the side surface 12, respectively. The side surface 12, the main flank surface 42, and the first sub flank surface 44 are formed such that lines of intersection between the three surfaces and the front surface 14 (or the back surface 16) are parallel to each other. That is, the normal vectors of the side surface 12, the main flank surface 42, and the first sub flank surface 44 are vectors within one plane.
The angle between the side surface 12 and the main flank 42 is about 48.5 degrees, and the angle between the side surface 12 and the first sub flank 44 is about 3.5 degrees.

The second sub-cutting edge 36 is a part of a line of intersection between the adjacent side surfaces 12 (referred to as a cutting edge line for convenience), and has a center line shown in FIG. 2 (a vertical direction in FIG. 2). From the intersection of the first sub-cutting edge 34 and the cutting edge line. In addition, the second auxiliary flank 4
Reference numeral 6 denotes a part of the side surface 12, which is a rectangular portion having a long side as a line of intersection between the side surface 12 and the first sub flank 44 and a short side as the second sub cutting edge 36. Part of the side surface 12 is a rake face 5
Used as 0. The rake face 50 occupies a diagonal position different from the diagonal position where the flank 40 is formed on the side surface 12. Whether each diagonal of the side surface 12 is the flank 40 or the rake surface 50 depends on the situation where the vertical chip 10 is used. For example, when used for a right milling cutter, the flank face 40 and the rake face 50 have the positions shown in FIGS. 1 and 2, but when used for a left milling machine, their positions just interchange. The cutting edge 30, flank 40 and rake face 50 are honed for protection.

FIG. 3 is a front view of a vertical chip according to a third embodiment of the present invention. The vertical chip 10 of the present embodiment is different from the vertical chip of the above-described embodiment in that:
Side 12 is smoothly curved near its center 54. With such a shape, the mechanical strength of the vertical die can be improved.

FIGS. 4 to 6 are views showing a milling machine according to an embodiment of the fourth invention. FIG.
FIG. 4 is an enlarged front view showing a portion where the vertical chip 10 is attached. FIG. 5 is a left side view thereof, and FIG.
Is a GHIJKL cross sectional view in the bottom view shown in FIG. The body 62 of the milling cutter 60 is provided with 18 chip mounting seats 64 for mounting the vertical chips 10 at equal intervals, and a bolt 66 is used for mounting the vertical chips 10 on the chip mounting seats 64. Is used. FIGS. 7 and 8 are enlarged views of a part (in a circle) of FIGS. 5 and 6, respectively. 7 and 8, the plurality of cutting edges 30 and the flank 4 of the vertical die 10 are shown.
0, the rake face 50 and the like are denoted by the reference numerals only for those parts that are used for actual machining while being attached to the milling cutter 60. That is, the parts with the reference numerals form one corner. The vertical chip of the present embodiment has seven other portions similar to the portions denoted by reference numerals in FIGS. 7 and 8. That is, eight corners can be used.

When the vertical chip 10 is attached to the milling cutter 60, as shown in FIG. 4, the axial rake γ _p is set to about 8 degrees, and the clearance angle α of the flank 40 is set to about 12 degrees. I have. Also, as shown in FIG.
Is about 43.5 degrees, the first sub cutting angle κ ₁ ′ of the first sub cutting edge 34 is about 1.5 degrees, and the second sub cutting angle κ ₂ ′ of the second sub cutting edge 36 is about 5 degrees. FIG.
As shown in the figure, the radial lake γ _f is set to about −10 degrees. Generally, a basic blade shape of a milling cutter in which the signs of the radial rake γ _f and the axial rake γ _p are different is referred to as a negative-positive type (NP type). In other words, the milling cutter 60 provided with the vertical mold tip 10 has a basic blade shape of a negative-positive type (NP type). NP type
This basic blade shape is advantageous when performing heavy cutting typified by rough cutting of steel or cast iron, or when it is necessary to discharge chips smoothly. When the cut object is a light alloy or non-metal, or a material having an easily formed cutting edge, the radial rake γ _f and the axial rake γ _p are both correct in order to further improve the sharpness. Double positive type (DP type). In the case of face milling, since the finished surface roughness is a problem, the blade shape is determined so that the portion located at the most distal end side of the cutting edge is almost parallel to the finished surface in a standard insert. .
Also in the vertical chip 10 of the present embodiment, the angle between the first sub-cutting edge 34 and the finished surface is reduced as described above.

FIGS. 9 and 10 are a front view and a right side view of a vertical chip according to another embodiment of the first and second aspects of the present invention. Vertical chip 1 of the present embodiment
0 denotes a chip body 70 whose front view and right side view are shown in FIGS. 11 and 12, and a high hardness piece 72 whose front view, plan view and right side view are shown in FIGS. 13 to 15, respectively.
The high hardness piece 72 is formed by brazing to the mounting seat 74 of the chip body 70. FIG. 12 is a sectional view taken along line MM ′ of FIG. The high hardness piece 72 is formed of a material having a higher hardness than the chip body 70. Cemented carbide is widely used as a chip material, but is generally not practical for high-speed cutting of steel, for example. For such applications, TiN cermet,
Materials such as ceramics are often used. CBN sintered compacts are used for cutting heat-resistant alloys and high-hardness materials, and diamond sintered compacts are used for cutting non-ferrous metals and non-metallic materials. Chips may also have disadvantages such as poor impact resistance. And in milling,
In addition to thermal abrasion, mechanical abrasion due to impact during processing may be a problem.

The shapes and configurations shown in FIGS.
For example, the chip body 70 is made of a cemented carbide having relatively high impact resistance, and the high hardness piece 72 is made of one of the above various materials.
This makes it possible to reduce the possibility that the entire chip cannot be used due to the loss of one cutting edge. As described above, in the present embodiment, it is possible to manufacture a chip that has a long life as a tool and that is compatible with various conditions such as processing conditions and a workpiece. The high-hardness pieces 72 are independent for each corner, but may be formed by integrating the high-hardness pieces 72 of two adjacent corners by sharing a part of the intersection line of the side surface 12. Good. In addition, the side surface 1 of the vertical chip 10 of this embodiment
2 may be curved similarly to the vertical tip of the embodiment shown in FIG. This case is an embodiment of the third invention.

FIGS. 16 to 18 are views showing a state where the vertical chip shown in FIGS. 1 and 2 is mounted on a chip mounting seat 64 formed on the cutting tool body 80. FIG. It is also possible to attach a vertical chip having a shape different from that shown in FIGS. 1 and 2, for example, the vertical chip 10 shown in FIGS. As described above, the vertical die according to the present invention can be used as a bite for a lathe or the like.

Although several embodiments have been described with reference to the drawings, the vertical chip, the milling cutter, the cutting tool, and the like according to the present invention are not limited to the shapes shown in the respective drawings. Also, the present invention can be implemented in various modified and improved forms based on the knowledge of those skilled in the art without departing from the scope of the claims.

[Brief description of the drawings]

FIG. 1 is a front view of a vertical chip which is one embodiment common to the first and second inventions of the present application.

FIG. 2 is a right side view of the vertical chip.

FIG. 3 is a front view of a vertical chip according to an embodiment of the third invention of the present application.

FIG. 4 is a front view showing a milling machine according to an embodiment of the fourth invention of the present invention.

FIG. 5 is a left side view of the milling machine.

FIG. 6 is a bottom view of the milling machine.

FIG. 7 is an enlarged view showing a part of FIG. 5;

FIG. 8 is an enlarged view showing a part of FIG. 6;

FIG. 9 is a front view of a vertical chip as another embodiment common to the first invention and the second invention of the present application.

FIG. 10 is a right side view (partially sectional view) of the vertical die of FIG. 9;

FIG. 11 is a front view showing a chip main body constituting the vertical chip shown in FIGS. 9 and 10;

FIG. 12 is a right side view (partially sectional view) of the chip body of FIG. 11;

FIG. 13 is a front view of a high-hardness piece constituting the vertical die shown in FIGS. 9 and 10;

FIG. 14 is a plan view of the high hardness piece of FIG.

FIG. 15 is a right side view of the high hardness piece.

FIG. 16 is a front view showing a cutting tool in which the vertical tip shown in FIGS. 1 and 2 is mounted on a cutting tool main body.

FIG. 17 is a plan view of the cutting tool.

FIG. 18 is a left side view of the cutting tool.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 vertical tip 12 side surface 14 front surface 16 back surface 18 mounting hole 20 first taper portion 22 second taper portion 30 cutting edge 32 main cutting edge 34 first sub cutting edge 36 second sub cutting edge 40 flank 42 main flank 44 first sub flank 46 second sub flank 50 rake face 54 near center 60 milling 62 body 64 chip mounting seat 66 bolt 70 chip body 72 high hardness piece 74 mounting seat 80 byte body

Claims (4)

[Claims] 1. A flat chip having a square front face and a mounting hole penetrating in the center, wherein each side of the square is depressed inward, so that adjacent side faces can be separated from each other. A vertical chip characterized in that the formed angle is an acute angle, and each of the side surfaces can be used as a rake face. 2. The vertical chip according to claim 1, wherein each side of the square is a bent line bent at a midpoint, and the mounting hole has a symmetrical shape with respect to a center in an axial direction. . 3. The method according to claim 3, wherein each side of the square has a concave curve that is smoothly curved at least at a central portion and is symmetrical with respect to a center point, and the mounting hole is formed with a symmetrical shape with respect to an axial center. The vertical chip according to claim 1, characterized in that: 4. A bolt inserted into the mounting hole, wherein the vertical chip according to claim 1 is seated on a plurality of chip mounting seats formed at the tip of the outer peripheral surface of the body. A milling cutter characterized by being fixed by: