JP3003230B2 - Indexable inserts and indexable cutters - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a flat-shaped insert insert, in which one of upper and lower surfaces facing the thickness direction is a flank facing the tool outer peripheral side, and the other is a seating surface for the tool body. Inserts and throw-away tools suitable for use in so-called vertical blade milling cutters, etc.
About tta .

[0002]

2. Description of the Related Art Conventionally, a so-called vertical blade milling tool has been used for cutting work requiring high rigidity such as cutting difficult-to-cut materials. In this vertical blade type milling machine, a flat throw-away tip (hereinafter, abbreviated as a tip) is provided on an outer peripheral portion of a tip end of a tool main body, and one of upper and lower surfaces facing the thickness direction faces the outer peripheral side of the tool. It is attached so that it becomes a flank. In this vertical blade milling machine, while the other of the upper and lower surfaces of the chip is a seating surface that is in close contact with the bottom surface of the chip mounting seat of the tool body, any one of the side surfaces arranged around these upper and lower surfaces is used. The rake face is oriented in the tool rotation direction, and the main cutting edge formed at the intersection ridge line between the rake face and the flank face of the tip cuts the workpiece with the rotation of the tool body. . In addition, as a specific shape of a tip used in such a vertical blade milling machine, a shape generally having a substantially square shape in a plan view from a direction perpendicular to the upper and lower surfaces is generally used. In many cases, the side surface is formed as a uniform plane in consideration of the adhesion between the tool body and the side surface of the chip mounting seat.

[0003]

By the way, such a vertical-type milling cutter receives a cutting load applied to the main cutting edge in the width direction of the insert at the time of cutting, so that the rigidity of the insert obtained with the tool mounted is high, and Since the depth of the tip mounting seat to be formed on the tool body side in the tool radial direction is only about the thickness of the tip, the rigidity of the tool body is lower than that of the conventional milling cutter that has one of the upper and lower surfaces as a rake face. Get higher,
As a result, high feed and high speed cutting of difficult-to-cut materials can be performed. However, when high-feeding and high-speed cutting are performed, the amount of chips generated accordingly increases, so that a high degree of chip discharging property is required. In this respect, in particular, in the case of a conventional chip in which the side surface is formed in a uniform plane, a single wide plate-like chip is formed over the entire length of the main cutting edge and extends as it is, so that the chip discharge property is sufficient. It was hard to say.

[0004] In addition, when cutting a work material having a hard layer on the surface such as a casting, there is a demand for reducing the cutting resistance by changing the axial rake angle of the main cutting edge in a regular angle direction. On the other hand, on the rear end side of the main cutting edge for cutting the hard layer, there is a demand to improve the edge strength of the main cutting edge to improve the durability of the insert. In the case of a conventional tip formed on such a flat surface, the axial rake angle of the main cutting edge becomes uniform, and thus the requirements of the two cannot be satisfied.

The present invention has been made in view of the above circumstances, and when used in a vertical-blade milling machine or the like , it is possible to enhance the chip discharge performance and to increase the strength of the cutting edge on the rear end side of the main cutting blade. Indexable insert and indexable type that can reduce the cutting resistance at the tip of the main cutting edge while maintaining
The purpose is to provide a cutter .

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention has a polygonal flat plate shape and faces in the thickness direction.
One of the upper and lower surfaces is a flank and the other is the
The seating surface is in close contact with the
A throwaway where the side to be placed is a rake face
In the chip, place each side on both sides in the longitudinal direction of each side.
The flat surfaces arranged, and the flat surface
From the intersection with the flat surface toward the center of the side
Composed of a concave surface that gradually depresses
The concave surface is formed perpendicular to the upper and lower surfaces, and the concave surface and the flank
The main cutting edge is formed at the intersection ridge line portion. Ma
The indexable cutter according to the present invention is a tool body.
A throwaway tip is attached to the outer periphery of the tip of
This throw-away tip has a polygonal plate shape,
One of the upper and lower surfaces facing the thickness direction is used as a seating surface
It is attached to the tip mounting seat of the body, and the other of the upper and lower surfaces is
The side face located between these upper and lower faces is a rake face.
The side of this indexable cutter is
Flat surfaces arranged at both ends in the longitudinal direction of the side surface, and these flat surfaces
Concave curved surface disposed between flat surfaces and depressed with respect to the flat surface
The flat surface and the concave surface are perpendicular to the upper and lower surfaces.
Main cutting edge is formed at the intersection ridge line between the concave curved surface and the flank
This main cutting edge has an axial rake angle
It is arranged so that it has a positive angle at the end and a negative angle at the rear end.
It is characterized by having.

[0007]

The throw-away tip and the thrower having the above structure are provided.
According to the way-type cutter , the bending action acts on the chip by the concave rake face, so that the chip is easily deformed as compared with the conventional example in which the flat chip is generated, and the chip discharging property is improved. In addition, on the tip side of the main cutting edge, the axial rake angle is a regular angle due to the concave surface, so that sharpness is improved. On the other hand, on the rear end side of the main cutting edge, the axial rake angle is negative due to the concave surface.
In edge strength is increased.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In these figures, reference numeral 1 denotes a chip according to the present embodiment. As shown in detail in FIG. 1 to FIG.
The upper surface 2 and the lower surface 3 which are parallel to each other and have the same shape are formed in the thickness direction thereof in a flat plate shape having two corner portions C. As shown in more detail in FIGS. 2 to 5, the center of these upper and lower surfaces 2, 3 is
Both ends of a mounting hole 4 extending in the thickness direction of the chip 1 are opened. The mounting hole 4 is a hole through which a clamp screw 7 for mounting the chip 1 on a chip mounting seat 6 of a tool body 5 described later is inserted.

Further, four side surfaces 8 are formed around the upper and lower surfaces 2, 3. Each of the side surfaces 8 is composed of two flat surfaces 9.9 arranged at both ends of each side surface 8 and orthogonal to the upper and lower surfaces 2 and 3, and each flat surface 9 disposed between these flat surfaces 9. 1 is gradually depressed toward the center of the chip 1 from the intersection toward the center of the side surface 8 in the longitudinal direction.
(FIG. 1, FIG. 1).
3 and 5). Here, the positional relationship between the two flat surfaces 9 constituting one side surface 8 is determined such that the extension surface of one flat surface 9 overlaps the other flat surface 9. The flat surface 9 of each side surface 8 is made orthogonal to the flat surface 9 of the adjacent side surface 8. Therefore, the corner angles in a plan view from the direction orthogonal to the upper and lower surfaces 2 and 3 of the chip 1 are all 90 °. Have been. The length S (see FIG. 2) of each flat surface 9 in the longitudinal direction of the side surface is appropriately set according to the length of one side of the upper and lower surfaces 2, 3 and cutting conditions. It is set to 85 mm. However,
The length S of the flat surface 9 may be changed at one end and the other end of each side surface 8, and the length S of the flat surface 9 may be different for each side surface 8.

On the other hand, the concave curved surface 10 is formed as a circular arc surface which is curved toward the center of the chip 1 with a constant radius of curvature R (see FIG. 2). 1 is greatly depressed toward the center. Further, each concave curved surface 10 includes upper and lower surfaces 2 of the chip 1,
3 is perpendicular to the upper and lower surfaces 2 and 3 in a cross section orthogonal to the upper surface 2 (hereinafter, referred to as a thickness direction cross section), whereby the radius of curvature R of the concave curved surface 10 is changed from the intersection with the upper surface 2 in the chip thickness direction. Along the lower surface 3 until the intersection. A main cutting edge 11 is formed at the intersection ridge line between the concave curved surface 10 and the upper and lower surfaces 2 and 3.

Here, the curvature radius R of the concave curved surface 10 is appropriately changed according to the length of one side of the upper and lower surfaces 2 and 3 and the cutting conditions, similarly to the length S of the flat surface 9 described above. In this embodiment, R is set to 10 mm. Further, as shown in FIG. 2, the angle (hereinafter, referred to as a contact angle) θ between the tangent L at both ends of the concave curved surface 10, that is, at the intersection with the flat surface 9, is set to 26 ° 45 ′. I have. In addition,
These values do not need to be equal for all the side surfaces 8, and may be different values for each side surface 8.

Further, as shown in more detail in FIG. 1, a flat surface 9 is formed at the intersection ridge line between each flat surface 9 and the upper and lower surfaces 2 and 3.
And an auxiliary flank 12 intersecting at an obtuse angle with one of the upper and lower surfaces 2 and 3. These auxiliary flank surfaces 12 are formed by obliquely chamfering the intersection ridges of the flat surface 9 and the upper and lower surfaces 2 and 3 with a processing means such as a grindstone.
The chips 1 are arranged so as to intersect the upper and lower surfaces 2 and 3 alternately along the circumferential direction. And each sub-flank 12
Has a flat surface 9 on another side surface 8 adjacent to one flat surface 9 cut out by each sub-flank surface 12. That is, the sub flank 12a located at the lower left end side in FIG. 1 will be described as an example.
a reaches the flat surface 9b of the other side surface 8 adjacent to the one flat surface 9a cut out by the sub flank surface 12a, and similarly, the other sub flank surfaces 12 The longitudinal end reaches the adjacent flat surface 9. On the other hand, the rear end of each sub flank 12 in the longitudinal direction is a concave curved surface 1.
It has reached zero. A sub-cutting edge 13 is formed at a crossing ridge of each of the sub-flanks 12 at the longitudinal end and the flat surface 9.

Next, the operation of the chip 1 having the above structure will be described. Prior to this, the structure of the tool body 5 on which the chip 1 is mounted will be briefly described first, and thereafter, the chip 1 will be mounted. The operation in a state where the camera is in a closed state will be described.

As shown in FIG. 6 to FIG.
Is formed in an annular shape, and a large number of chip mounting seats 6 for mounting the chip 1 are formed at equal intervals in the circumferential direction on the outer peripheral portion on the tip side in the axial direction. These tip mounting seats 6 include a bottom surface 6a facing the outer peripheral side of the tool and a bottom surface 6a.
The bottom surface 6a is formed as an inclined surface that gradually recedes toward the center in the tool radial direction from the rear end side in the tool axis direction toward the front end side. I have. On the other hand, as shown in more detail in FIGS. 7 and 8, the second wall surface 6c is gradually inclined toward the tool rotation direction (the direction of arrow A in FIG. 7) from the front end side to the rear end side in the tool axis direction. It is formed in a planar shape,
The first wall surface 6b is orthogonal to the second wall surface 6c. Further, the tool mounting direction side of the tool main body 5 with respect to the chip mounting seat 6 (the direction of arrow A in FIG. 1).
A chip pocket 15 is formed at a position adjacent to the tip pocket 15 to be depressed toward the center in the tool radial direction.

As shown in more detail in FIG. 1, the above-mentioned tip 1 is provided to the tool body 5 having the above-described structure, and the tool body 5 has one of the upper and lower surfaces 2 and 3 (in the case where the upper surface 2 is selected in FIG. 1). Is selected as a flank facing the outer peripheral side of the tool, and the other is selected as a seating surface that is in close contact with the bottom surface 6a of the chip mounting seat 6, and inserted into the chip mounting seat 6, and thereafter,
It is tightened by the clamp screw 7 and attached to the tool body 5. At this time, a predetermined corner angle φ (see FIG. 6) is given to the upper surface 2 selected as the flank along the inclination of the bottom surface 6 a of the chip mounting seat 6, whereby the auxiliary surface facing the tip side in the tool axial direction is provided. The cutting edge 13 is made substantially orthogonal to the tool axis. 7, the tip 1 is inclined according to the inclination of the first and second wall surfaces 6b, 6c of the tip mounting seat 6 with respect to the tool axis, and specifically, the side protruding toward the tool tip side. The side that comes into contact with the first wall surface 6b is made to protrude in the tool rotation direction more than the first wall surface 6b.

When the chip 1 is mounted in the above-described state, one of the four side surfaces 8 becomes one of the chip pockets 15.
The main cutting edge 11 along the side surface 8 selected as the rake face cuts a work material (not shown) as the tool body 5 rotates around the axis. At this time, since the rake face of the main cutting edge 11 is a concave curved surface 10, chips generated from the main cutting edge 11 intersect with the main cutting edge 11 while being constantly bent by crossing the concave curved surface 10. Grow in the direction. Therefore, as compared with the conventional example in which flat chips are generated, the deformation of the chips is large, and as a result, the chip discharge performance is improved.

Since the main cutting edge 11 is curved by the concave curved surface 10, the axial rake angle of the main cutting edge 11 continuously changes along the tool axis direction, and the main cutting edge 11 in the tool axis direction is changed. The axial rake angle on the front end side changes in a more regular angle direction than the central portion of the main cutting edge 11, while the axial rake angle on the rear end side in the tool axis direction of the main cutting edge 11 changes in the negative angle direction. Therefore, while the sharpness is improved at the front end side of the main cutting edge 11 and the cutting resistance is reduced, the cutting edge strength is improved at the rear end side of the main cutting edge 11, and particularly, when the hard layer remains on the surface such as a casting. When cutting a material, a relatively soft inside is cut on the tip side of the main cutting edge 11 having a good sharpness to improve cutting efficiency, and at the same time, a surface layer of a work material having high hardness has high strength. An excellent effect that the durability of the tip 1 can be improved by cutting at the rear end side of the main cutting edge 11 is obtained.

In addition, since flat surfaces 9 are left at both ends of the side surface 8 of the chip 1, the flat surfaces 9 and the first and second wall surfaces 6b and 6c of the chip mounting seat 6 are closely contacted. Accordingly, the chip 1 can be stably supported, so that the mounting rigidity of the chip is not impaired at all. Incidentally, when the entire side surface 8 is formed into a concave curved surface, or when a flat surface is left only at one end of the side surface 8, the chip 1 is stabilized by the wall surfaces 6b and 6c of the chip mounting seat 6 having a planar shape. And various problems such as induction of chatter vibration are likely to occur.

In this embodiment, the shape of the chip in plan view is particularly a substantially square shape having four corners.
The present invention is not limited to this, and various modifications such as a triangular shape are possible. Further, in the present embodiment, the concave surface disposed on the center side of the side surface 8 is the concave curved surface 10 which is depressed in an arc shape inward of the chip. However, the present invention is not limited to this, and the present invention is not limited to this. An inclined surface that inclines linearly,
Further, it may be formed in a multi-stage surface shape that is bent in multiple stages.

[0020]

As described above, as described above, the thrower of the present invention
According to the way tip and the throw-away type cutter , since the chips generated from the main cutting edge by the concave surface grow while being subjected to the bending action, the deformation of the chips is increased and the chip dischargeability is improved. In addition, since the main cutting edge is formed along the concave surface, the axial rake angle on the front end side of the main cutting edge is a regular angle, and the sharpness is improved, and the axial rake angle on the rear end side of the main cutting edge is increased. At a negative angle, the cutting edge strength is improved. Therefore, when cutting a work material having a hard layer on the surface, such as a casting, the cutting resistance is reduced by cutting the inside of the work material at the tip side of the main cutting blade, and at the same time, the main cutting edge is reduced. By cutting the surface layer of the work material at the rear end side of the blade, the durability of the chip can be improved. In addition, since flat surfaces are left particularly at both ends of the side surface of the chip, these flat surfaces are securely brought into close contact with the wall surface of the chip mounting seat of the tool main body, so that the mounting rigidity of the chip can be sufficiently ensured.

[Brief description of the drawings]

FIG. 1 is an enlarged view of a state in which a tip according to an embodiment of the present invention is mounted on a tool main body when viewed from the outer peripheral side of the tool.

FIG. 2 is a front view of the chip according to the embodiment.

FIG. 3 is a view as seen from the direction of arrow III in FIG. 2;

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 2;

FIG. 5 is a perspective view of the chip shown in FIG. 2;

FIG. 6 is an axial sectional view of a tool main body.

FIG. 7 is a view as seen from the direction of the arrow VII in FIG. 6;

FIG. 8 is a view as seen from the direction of arrow VIII in FIG. 6;

9 is a sectional view taken along line IX-IX in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Throw-away insert 2 Upper surface 3 Lower surface 5 Tool body 6 Tip mounting seat 8 Side surface 9 Flat surface 10 Concave curved surface 11 Main cutting edge 12 Sub flank 13 Sub cutting edge

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-216615 (JP, A) JP-A-2-284804 (JP, A) JP-A-59-146710 (JP, A) 127816 (JP, U) Japanese Utility Model Showa 59-34915 (JP, U) Japanese Utility Model Showa 62-123803 (JP, U) Japanese Utility Model Utility Model 1-87818 (JP, U) (58) Field surveyed (Int. ⁷ , DB name) B23C 5/20 B23C 5/06

Claims (4)

(57) [Claims] 1. A polygonal flat plate, wherein one of upper and lower surfaces opposed in a thickness direction is a flank, and the other is a seating surface which is in close contact with a chip mounting seat of a tool body, and is disposed between the upper and lower surfaces. In the throwaway chip in which the side face to be disposed is a rake face, the side faces are each provided with a flat face disposed at both longitudinal ends of each side face, and a flat face disposed between the flat faces. The flat surface and the concave surface are formed by a concave surface that gradually depresses gradually from the intersection with the flat surface toward the center of the side surface.
A throw-away insert formed at right angles to the upper and lower surfaces , wherein a main cutting edge is formed at an intersection ridge line between the concave curved surface and the flank . 2. The indexable insert according to claim 1, wherein an intersection of the flat surface and the upper and lower surfaces intersects one of the upper and lower surfaces and the flat surface at an obtuse angle, and a tip is adjacent to the flat surface. A throwaway tip, wherein a sub-flank reaching another flat surface intersecting with the second flat surface is formed, and a sub-cutting edge is formed at an intersection ridge portion between the sub-flank and the other flat surface. 3. A throw-away lance on the outer periphery of the tip of the tool body.
This throw-away tip has many
One of the upper and lower surfaces that is in the form of a rectangular plate and faces in the thickness direction
Is attached to the tip mounting seat of the tool body as a seating surface,
The other of the upper and lower surfaces is a flank and is located between these upper and lower surfaces.
Indexable cutter with rake face
In the above, the side faces are arranged at both ends in the longitudinal direction of the side faces.
Between the flat surface and the flat surface
The flat surface and the concave surface.
Are formed perpendicular to the upper and lower surfaces, the concave curved surface and the flank surface
Is main cutting edge is formed at the intersection ridgeline portion between, the main cutting edge is axial rake angle at the tip end of the tool body
It is arranged to be a positive angle and a negative angle on the rear end side
A throw-away type cutter characterized by the following. 4. A flat surface of the throw-away tip and a relief
A secondary flank is formed at the intersection with the flank,
Has a secondary cutting edge protruding toward the tip of the tool body
4. The throw-away bracket according to claim 3, wherein
Ta.