JPH04130114U - Throwaway end mill - Google Patents

Abstract

(57) [Summary] [Structure] A plurality of chip mounting seats 5 are formed in a row along the spiral groove 4 formed on the outer periphery of the tool body 1,
Peripheral indexable inserts 6 each having a cutting edge 11 are mounted with one end surface 8 thereof directed toward the outside in the radial direction of the tool body 1. A sloped surface 13 that slopes inward in the thickness direction of the indexable insert 6 for an outer peripheral knife is formed on the nose portion 12 that is continuous with the cutting edge 11 of the indexable insert 6 for a peripheral knife. A cutting blade 14 for inclined processing is formed at the ridge line formed by the inclined surface 13 and the one end surface 8. [Effect] It is possible to improve the strength of the cutting edge at the nose portion 29 of the indexable insert 6 for peripheral cutting edges, and it is possible to prevent chipping of the cutting edge especially in the case of inclined machining.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention has multiple indexable tips (hereinafter referred to as tips) on the outer periphery of the tool body. to be called. ) are spirally attached to form a peripheral cutting edge. This is related to LE.

0002

[Conventional technology]

Conventionally, such indexable end mills (hereinafter simply referred to as end mills) were used. Ru. ), for example, Utility Model Application No. 62-168210, or JP-A No. 63-2 The one described in No. 16615 is known.

0003 These end mills have a spiral groove formed on the outer periphery of the tool body. On the rear side, a plurality of chip mounting seats opening into the outer circumference of the tool and into the spiral groove are attached to the spiral groove. They are formed in a row along the spiral groove, and these insert mounting seats are made of cemented carbide, etc. The chip is removably attached. This chip is usually It has a polygonal flat plate shape, and a cutting edge is formed at the intersection ridge line formed by the end surface and the peripheral surface. There is. Then, for each row of chip mounting seats formed in the spiral groove, the chip mounting seats are machined. Narrow the pitch in the tool axis direction to the minimum and move each chip mounting seat in the tool circumferential direction. Slightly shift the tool axis rotation of the cutting edge in all rows of each insert seat. By making the rotation locus continuous in the tool axis direction, the cutting edge length of a single insert can be increased. A peripheral cutter with a length exceeding the length of the groove is formed for each spiral groove.

0004

[Problem that the idea aims to solve]

By the way, in cutting processing using such an end mill, the end mill In addition to cutting by moving the tool body only in the direction perpendicular to the tool axis, Cutting is performed while moving the tool body in the direction of the tool axis in addition to the direction perpendicular to the tool axis. In some cases, so-called inclined machining is performed. In such cases, a tool book Of the nose portions formed at both ends of the cutting edge of the tip attached to the outer periphery of the body, The nose portion on the side of the tool body in the moving direction is largely involved in cutting. However, the strength of the cutting edge near the nose is weak compared to other parts of the cutting edge. It is weak, and therefore there is a problem that damage etc. easily occur during cutting work. and this question The problem is that when the cutting edge is tiltable as mentioned above, in addition to the load on the cutting edge in the direction around the tool axis, This is particularly noticeable as the load in the direction of tool movement is applied. There was a risk that smooth cutting work would be hindered.

[0005]

[Means to solve the problem]

This invention was made to solve the above problem, and has a small amount on the outer periphery of the tool body. At least one spiral groove is formed, and on the rear side of this spiral groove in the direction of tool rotation. A plurality of chip mounting seats opening into the outer periphery of the tool body and the spiral groove are connected to the spiral groove. Each of these chip mounting seats has a polygonal A chip for peripheral blades that is flat in shape and has a cutting edge formed at the intersection ridge line formed by the end face and peripheral face. An end product in which the tip is attached with the end face facing outward in the radial direction of the tool body. In the tool, the nose part of the peripheral cutting tip connected to the cutting edge is An inclined surface that slopes inward in the thickness direction of the peripheral blade tip as it approaches the tip of the tip. A cutting edge for inclined processing is formed on the ridge line formed by this inclined surface and the above-mentioned end surface. It is characterized by:

[0006]

[Effect]

According to the present invention, an inclined surface is formed on the nose of the chip, and this inclined surface is By forming a cutting edge for inclined machining on the ridge line formed by the above-mentioned end surface of the chip, Cutting at the nose part during slope machining is done exclusively by this cutting blade for slope machining. It will be. Here, since the cutting edge angle of this cutting blade for inclined machining is an obtuse angle, The cutting edge strength can be increased compared to the nose part described above, and it is suitable for inclined machining as described above. It is possible to prevent damage to the cutting edge even if the cutting edge is damaged.

[0007]

【Example】 1 to 3 show an embodiment of the present invention. As shown in Figure 1 The tool body 1 of this embodiment has a substantially cylindrical shape, and a machine tool such as a milling machine is attached to the base end. While a shank 2 is formed for attachment to the A slightly larger diameter blade portion 3 is formed coaxially with the shank 2. The outer periphery of this blade part 3 is provided with multiple threads (actual threads) that are twisted at a constant angle around the tool axis O. In the example, four (4) spiral grooves 4 are formed at equal intervals in the circumferential direction, and these spiral grooves On the rear side in the rotational direction of the tool 4, there is a chinch that opens into the outer circumferential surface of the blade portion 3 and into the spiral groove 4. A plurality of (five in this embodiment) cup mounting seats 5 are arranged in a row along the spiral groove 4. is formed. These chip mounting seats 5 are shown in FIGS. 4 to 6. A peripheral cutting edge tip 6 like this is detachably attached using a mounting screw 7.

[0008] As shown in these figures, this peripheral blade tip 6 is a flat plate made of cemented carbide. It is shaped like a substantially equilateral triangle when viewed from the side of one end surface 8, and the other side is The end surface 9 is formed parallel to and similar to this one end surface 8, and the three peripheral surfaces 10 are It is a so-called positive type chip that forms an isosceles trapezoid when viewed from the side from the peripheral surface 10. A cutting edge 11 is formed at the intersection ridge line formed by the one end surface 8 and each circumferential surface 10. Ru. and noses located at each corner of the equilateral triangle formed by the one end surface 8 and sandwiching the cutting blade 11. In the portion 12, the thickness of the tip 6 is gradually increased toward the tip side of the nose portion 12. An inclined surface 13 facing inward in the direction is formed, and this inclined surface 13 and the above-mentioned A cutting blade 14 for inclined machining that intersects with the cutting blade 11 is formed on the ridge line formed by the one end surface 8. has been completed. Incidentally, here, the inclination angle α between this inclined surface 13 and the above-mentioned one end surface 8 is The angle is set at 5° to 30°, and the cutting blade 14 for inclined machining is set to the above-mentioned one end surface 8 side. When viewed from above, it faces the nose portion 12 on which the cutting blade 14 for inclined machining is formed. It is shaped to be parallel to the cutting edge 11. Furthermore, as shown in Figure 5, this trend The distance L between the cutting blade 14 for oblique machining and the tip of the nose portion 12 is set to 0.5 to 2.0 mm. It is.

[0009] On the other hand, the tip mounting seat 5 on which the tip 6 is attached is located from the outer peripheral surface of the blade portion 3. The bottom surface 15 is lowered one step, and the bottom surface 15 is raised toward the outer peripheral surface of the blade portion 3. It is composed of rising wall surfaces 16 and 17. The bottom surface 15 is made of chips other than the above-mentioned chip 6. It is formed into a triangular flat surface that can be closely attached to the end surface 9, and the wall surfaces 16 and 17 are From the rear apex side of the bottom surface 15 in the tool rotation direction toward the opening side to the spiral groove 4 Therefore, the chip mounting seats 5 are formed so as to be spaced apart from each other. is formed into a V-shape whose width increases toward the opening to the spiral groove 4. . Furthermore, the narrow angle of these wall surfaces 16 and 17 is the same as that formed by the end surfaces 8 and 9 of the chip 6. It is shaped at an angle equal to the apex angle of the triangle, ie 60°. And each tick The pipe 6 has the other end surface 9 connected to the bottom surface 15 and two of the three peripheral surfaces 10 connected to the wall surface 16. , 17, so that the first cutting edge 11 faces the spiral groove 4. and is further tightened with the mounting screw 7 to firmly attach it to the tool body 1. installed.

0010 In addition, the chip mounting seat 5 formed along each spiral groove 4 is It is gradually shifted forward in the direction of tool rotation from the tip of the tool to the base. At the same time, the tip is placed in the spiral groove 4 of the tip 6 mounted on the tip mounting seat 5. The axial rake angle of the facing cutting edge 11 with respect to the tool axis O is the helix angle of the helical groove 4. The torsion angle is also set to be larger, that is, to be more square than the torsion angle. is being kept. Furthermore, each chip mounting seat 5 has a maximum The tip is placed as close as possible in the direction of the tool axis O. The ends of the cutting edges 11 of each tip 6 attached to the tip 5 overlap by a predetermined amount in the direction of the tool axis O. It is designed to match each other. As a result, the outer periphery of the blade portion 3 is formed along each spiral groove 3. This results in the formation of four continuous outer circumferential cutting edges. In addition, the code 1 in the figure Reference numeral 8 denotes a relief portion for avoiding interference between the chip 6 and the chip mounting seat 5.

[0011] Furthermore, in this embodiment, a first bottom cutting tip is provided at the tip of each spiral groove 4 of the tool body 1. Two mounting seats 19 and two second bottom blade tip mounting seats 20 are provided in the circumferential direction of the tool body 1. They are formed at equal intervals and alternately, and each has a diamond-shaped flat bottom blade of the same shape. Chips 21 and 22 are removably mounted with mounting screws 23. In addition, this The apex angle φ of the rhombus formed by the end surfaces 24 and 25 of the bottom blade tips 21 and 22 is 60° to 8 It is set to 0°. Here, the first bottom blade tip mounting seat 19 has a bottom blade tip 21 attached thereto. The one end surface 24 of the is formed so as to face the tip side in the direction of the tool axis O, while the second end surface 24 of the The bottom blade tip mounting seat 20 is attached to the one end surface 25 of the bottom blade tip 22 attached thereto. are formed so as to face the outer circumferential side of the tool, and these bottom cutting tips 21, 2 2 is attached, each of the bottom blade tips 21 and 22 is The cutting edges 26 and 27 formed on the ridge line are both similar to the cutting edge 11 of the peripheral edge tip 6. It is designed to face forward in the direction of rotation. Then, the first bottom blade tip remover One cutting edge 26 of the bottom blade tip 21 attached to the attachment seat 19 and the second bottom blade tip The other cutting edge 27 of the bottom edge tip 22 attached to the top mounting seat 20 is attached to the tool body 1. The first bottom edge tip 6 faces the outer periphery and is connected to the cutting edge 11 of the outer edge tip 6. The other cutting edge 27 of the bottom blade tip 21 attached to the top mounting seat 19 and the second bottom One cutting edge 26 of the bottom blade tip 22 attached to the blade tip mounting seat 20 is attached to the tool base. It is configured to face the tip of the body 1 and serve as the bottom blade of the end mill. Furthermore, the bottom blade tips 21 and 22 are attached to the bottom blade tip mounting seats 19 and 20. Key grooves 28 and 29 are respectively formed on the other end surface where the seat is seated, and one is for attaching the tip for the bottom blade. Keys 30 and 31 are formed in positions corresponding to the key grooves 28 and 29 of the seats 19 and 20. When these key grooves 28, 29 and keys 30, 31 engage, This prevents the bottom blade tips 21 and 22 from steadying.

0012 According to the end mill having the above configuration, the nose portion 12 of the tip 6 for the peripheral cutter is inclined. The surface 13 is formed, and the ridgeline formed by the sloped surface 13 and one end surface 8 of the chip 6 is sloped. By forming the cutting blade 14 for inclined machining, the cutting edge angle of the cutting blade 14 for inclined machining is obtuse. Since it is a corner, the strength of the cutting edge in the nose portion 12 can be improved. Therefore, in the case of inclined machining as described above, the load in the tool rotation direction is applied to the nose portion 12. Even if a load is applied in the moving direction of the tool body 1 in addition to the It is possible to prevent situations such as chipping, and smooth cutting work is possible. At the same time, the life of the chip can be extended.

[0013] Here, in the end mill having the above configuration, the cutting blade 11 installed in the direction of the tool axis O is A cutting blade 14 for inclined machining is formed on each of the two sandwiched nose portions 12 . Therefore, during inclined machining, the tool body 1 is moved toward the tip end in the axial direction while cutting. When performing this, the cutting edge 13 for inclined machining on the tool tip side of the cutting edge 11 is used exclusively for that nozzle. When moving the tool body 1 toward the proximal end in the axial direction during cutting in the vicinity of the gap portion 12, In this case, the cutting edge 13 for inclined machining on the tool base end side of the cutting edge 11 is exclusively used for cutting the nose portion 12 of the cutting edge 11. This will affect nearby cutting. Therefore, no matter which direction the tool body 1 is moved to perform inclined machining, the nose portion It becomes possible to effectively prevent damage to the cutting edge at 12.

[0014] In this embodiment, the angle of inclination between the one end surface 8 of the chip 6 and the inclined surface 13 is α was set to 5° to 30°, but this means that if the inclination angle α becomes smaller than 5°, the inclination The cutting edge angle of the cutting blade 14 for oblique machining may become too large and the cutting edge may become dull. On the other hand, when the inclination angle α is larger than 30°, the blade of the cutting blade 14 for inclined machining As the point angle becomes smaller, the strength of the cutting edge may also become smaller. It's a good thing. In addition, in this embodiment, the cutting blade 14 for inclined machining and the tip of the nose portion 12 are The distance L between the If the size exceeds the limit, the size of the slope 13 will become too large and the length of the cutting edge 11 will become too large. This is because the distance L becomes shorter, and conversely, if the distance L becomes smaller than this range, , the inclined surface 13 also becomes smaller and the cutting blade 14 for inclined machining cannot be formed with a sufficient length, This is because the above-mentioned effects cannot be obtained.

[0015] Furthermore, in this embodiment, both the one end surface 8 of the chip 6 and the above-mentioned inclined surface 13 are flat. Regarding the case where the ridge line where the cutting blade 14 for inclined machining is formed has a clear straight line shape. However, this configuration does not necessarily have to be used. For example, the above The end surface 8 and the inclined surface 13 are connected by a smooth curved surface, or The surface 13 itself may be a curved surface that smoothly connects to the end surface 8. In these cases , this curved surface exhibits the effect of a cutting blade for inclined machining.

[0016] Furthermore, in this embodiment, the peripheral blade tip 6 is described as having a triangular flat plate shape. However, it goes without saying that the present invention is not limited to this. More screws The number of threads of the spiral groove 4 and the number of chips 6 attached to one spiral groove 4 can be adjusted as necessary. can be set.

[0017]

[Effect of the idea]

As explained above, according to the present invention, the cutting at the nose part of the tip for the peripheral cutting edge is It is possible to improve the strength of the cutting edge of the blade. This makes it especially easy for inclined machining. Even if the cutting edge is damaged, it is possible to prevent damage to the cutting edge and prevent smooth cutting. At the same time, it is possible to extend the life of the chip.

[Brief explanation of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is an enlarged view of the tip portion of the embodiment shown in FIG. 1;

FIG. 3 is a view of the tool tip surface of the embodiment shown in FIG. 1,
FIG. 3 is a front view seen in the X direction in FIG. 2. FIG.

4 is a plan view of a peripheral blade tip 6 attached to the embodiment shown in FIG. 1. FIG.

5 is a side view of the chip 6 shown in FIG. 4 as viewed in the Y direction.

6 is a side view of the chip 6 shown in FIG. 4 as viewed in the Z direction.

[Explanation of symbols]

1 Tool body 4 Spiral groove 5 Peripheral cutter insert mounting seat 6 Peripheral cutter insert 8 One end surface of the insert 6 9 Other end surface of the insert 6 10 Peripheral surface 11 of the insert 6 Cutting edge 12 Nose portion 13 Inclined surface 14 Cutting for inclined machining Blade O Tool axis α Inclination angle L between one end surface 8 of the peripheral cutting tip 6 and the inclined surface 13 Distance between the cutting blade 14 for inclined processing and the tip of the nose portion 12

Claims (1)

[Scope of utility model registration request] 1. At least one spiral groove is formed on the outer periphery of the tool body, and on the rear side of the spiral groove in the tool rotation direction, a plurality of chip mounting seats are formed on the outer periphery of the tool body and open into the spiral groove. are formed in a row along the spiral groove, and each of these chip mounting seats has an outer periphery that is shaped like a polygonal flat plate and has a cutting edge formed at the intersection ridge line formed by the end face and the peripheral face. In an indexable end mill in which the indexable tip for a blade is attached with the end face facing outward in the radial direction of the tool body, a nose portion of the indexable indexable tip for a peripheral blade that is connected to the cutting edge has a nose portion that is connected to the cutting edge. An inclined surface is formed that slopes inward in the thickness direction of the indexable insert for the outer peripheral edge toward the tip of the part, and a cutting blade for inclined processing is formed on the ridge line formed by this inclined surface and the end surface. This indexable end mill is characterized by: