JP2833239B2 - Indexable tip - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throw-away insert used for a vertical blade milling cutter, and more particularly to a throw-away insert suitable for use in a finishing mill.

[0002]

2. Description of the Related Art Conventionally, as this type of throw-away chip (hereinafter, abbreviated as a chip), for example, the one described in Japanese Utility Model Laid-Open Publication No. 63-53612 is known. As shown in FIGS. 10 and 11, this chip has four side surfaces 3 arranged around the upper and lower surfaces 1 and 2,
Is a so-called positive tip inclined in a direction intersecting at an acute angle with respect to the upper surface 1, and a convex curved surface 4 is formed at a portion intersecting the upper surface 1 of each side surface 3, thereby protruding at an intersection ridge line portion between the upper surface 1 and each side surface 3. An arc-shaped finishing blade 5 is formed. At each corner where each side surface 3 intersects, a notch surface 6 whose width is gradually reduced from the upper surface 1 to the lower surface 2 is formed, and an outer peripheral blade 7 is formed at a ridge line between the notch surface 6 and the side surface 3.
Are formed.

As shown in FIGS. 12 and 13, a chip having such a configuration has one finishing blade 5 projecting substantially in parallel from the tip end surface of a tool body 8 and one outer blade 7 having a tool body 8 with a peripheral body 7. Is mounted on the tip mounting seat 9 of the tool body 8 in a detachable manner by bolts (not shown) in a state of protruding to the outer peripheral side of the tool.
Thus, the upper surface 1 connected to the finishing blade 5 is a front flank facing the tip side of the tool body 8, while the one side surface 3 connected to the finishing blade 5 is a rake surface facing the tool rotation direction. The notched surface 6 connected to one outer peripheral blade 7 protruding to the outer peripheral side of the tool is located on the tool rotation direction side of the outer peripheral blade 7 and is a rake surface of the outer peripheral blade 7.

[0004] In the above state, the insert is inserted into the tool body 8.
Is rotated around the tool axis, and the outer peripheral blade 7 cuts off a predetermined allowance left on the work material.
Further, the finishing blade 5 processes the work material into a plane.

[0005]

In the prior art described above, the notched surface 6 intersecting the side surface 3 of the chip at an obtuse angle is used as a rake surface of the outer peripheral blade 7, and the side surface 3 connected to the finishing blade 5 is used as the outer peripheral surface. Since the outer blade 7 is mounted on the tool main body 8 in a state where the side is inclined so as to retreat to the opposite side to the tool rotation direction, the radial rake angle of the outer peripheral blade 7 becomes a remarkably negative angle and the axial rake angle also becomes a negative angle. For this reason, there is a defect that the sharpness of the outer peripheral blade 7 is extremely poor, and the cutting resistance is increased, so that chatter vibration is large and it is easy to grow.
The present invention has been made based on the above circumstances, and an object of the present invention is to provide a chip capable of improving the sharpness of an outer peripheral blade during finish cutting and suppressing chatter vibration.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a corner portion of a front flank which is located at one end of a finishing blade from a direction perpendicular to the front flank. In a plan view, a cutout surface intersecting at an obtuse angle with one end of the finishing blade is formed, and an outer peripheral blade is formed at an intersection ridge line portion between the cutout surface and a positive rake face for the finishing blade.

[0007]

According to the above construction, since the outer peripheral edge is formed at the intersection of the notch surface and the positive rake surface with respect to the finishing blade, the positive rake surface with respect to the finishing blade is used as the rake surface of the outer peripheral blade. In common, the notched surface can be used as an outer peripheral flank for the outer peripheral blade. For this reason, the radial rake angle of the outer peripheral blade can be set to a negative angle in a range smaller than the conventional case, so that the sharpness of the outer peripheral blade can be improved.

[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 10 denotes a chip according to the present embodiment. The tip 10 is made of a cemented carbide material as a whole and is formed in a substantially rectangular flat plate shape. As shown in FIG. On the front flank 12 facing the side, the lower surface is a mounting surface 13 for the tool body 11.

As shown in FIGS. 1 and 2, the front flank 1
Four side surfaces 14 are provided around 2. These side surfaces 14 are provided on the side intersecting with the front flank 12 and have an arc rake surface 15 which protrudes in an arc shape outside the chip;
A flat rake face 16 is provided on the side intersecting with the mounting face 13 and extends flat in the longitudinal direction. As shown in more detail in FIG. 3, a finishing blade 17 is formed at an intersection ridge portion between the arc rake face 15 and the front flank 12, and the finishing blade 17 is chipped with the curvature of the arc rake face 15. A relatively large radius of curvature R outward of 10
It is formed in the shape of a curved blade which is curved by. In addition, finishing blade 1
7 is formed on all the ridges of the front flank 12 and the four side surfaces 14 in the present embodiment, but the present invention is not limited to this, and only one side of the front flank 12 or two It may be changed as appropriate, such as forming only on the sides.

Further, as shown in FIG. 4, each of the rake faces 15 and 16 constituting the side face 14 is directed from the front flank 12 to the mounting face 13 along the chip thickness direction. It is formed on a positive rake face that gradually recedes toward the center of the chip 10. Angles (hereinafter, referred to as chip rake angles) γ1 and γ2 formed by the rake faces 15 and 16 with respect to a plane orthogonal to the front flank 12 are appropriately determined according to the material of the work material, cutting conditions, and the like. In the illustrated example, γ1 <γ2, that is, the chip rake angle γ1 of the arc rake face 15 is equal to the chip rake angle γ of the flat rake face 16.
It is determined to be smaller than 2; specifically, γ1 is preferably in the range of 1 ° to 15 °, and γ2 is preferably in the range of 5 ° to 20 °.

As shown in FIGS. 1 to 5, notch surfaces 18 are formed at all corners C of the front flank 12. These notches 18 are formed so that each corner C of the front flank 12 located at one end of each finishing blade 17 forms an obtuse angle with one end of each finishing blade 17 in a plan view from a direction orthogonal to the front flank 12. It is notched in the direction intersecting with θ, and its planar shape has a triangular shape. Then, among the ridge portions of the notch surface 18, each finishing blade 17
The finishing blade 17 is provided on the ridge line with the arc rake face 15 corresponding to
Is formed at an obtuse angle. These outer peripheral blades 19 are provided with a notch surface 18 and a front flank 12.
When viewed from the direction along the intersection ridge line (see FIG. 5), it is inclined by a predetermined inclination angle φ with respect to the direction orthogonal to the front flank 12. The inclination angle φ is set so as to correspond to a corner angle when the tip 10 is mounted on the tool body 11.

Here, the width S occupied by the outer peripheral blade 19 in a direction perpendicular to the front flank 12, that is, in a chip thickness direction (FIG. 2)
And FIG. 5) is appropriately determined according to the cutting conditions such as the material of the work material and the cutting depth of the outer peripheral edge 19, but 0.2 mm
A range of 1.0 to 1.0 mm is preferably used. In this embodiment, notch surfaces 18 are formed in all corners C of the front flank 12.
However, the present invention is not limited to this. For example, when the finishing blade 17 is formed only on one side of the front flank 12, one end of the finishing blade 17 is provided. The number of finishing blades 17 to be formed, such as the formation of the notch surface 18 and the outer peripheral blade 19, can be changed as appropriate.

Next, the chip 10 constructed as described above
Will be described, but prior to this, the tip 10
The configuration of the tool main body 11 to which is mounted will be briefly described.

As shown in FIG. 6 and FIG.
Is formed in a substantially cylindrical shape with an enlarged front end side, and a plurality of chip pockets 21 and a chip mounting seat 22 are formed on the outer peripheral side of the front end at appropriate intervals in the circumferential direction. As shown in more detail in FIGS. 8 and 9, the chip mounting seat 22 has a bottom surface 22 a that is in close contact with the mounting surface 13 of the chip 10, and side wall surfaces 22 b and 22 c that are in close contact with two adjacent side surfaces 14 of the chip 10. The bottom 22
“a” is formed in an inclined surface shape that recedes at a predetermined angle β from a direction parallel to the tool tip surface 11a toward the tool rear end side in a direction opposite to the tool rotation direction (the direction of arrow A in FIG. 7).

In order to mount the chip 10 on the tool body 11 configured as described above, as shown in FIGS. 7 to 9, the chip 10 is mounted with the chip 10 inserted into the chip mounting seat 21. The clamp screw 23 is inserted into the hole 10a, and the clamp screw 23 is inserted into the screw hole 11 of the tool body 11.
b, the mounting surface 13 and the side surface 14 of the chip 10 are attached to the bottom surface 22a, the side wall surfaces 22b, and 22c of the chip mounting seat 22.
To each other. As a result, one finishing blade 17 of the tip 10 is made to protrude from the tip mounting seat 22 in the tool rotation direction and the tool axis direction, and one outer blade 19 intersecting one end of the finishing blade 17 is located on the outer peripheral side of the tool. It is protruded. Further, one side surface 14 which is a rake surface of the finishing blade 17 is also a rake surface for the outer peripheral blade 17 at the same time,
The notch surface 18 connected to the outer peripheral blade 19 is an outer peripheral flank for the outer peripheral blade 19. After the tip 10 is mounted in the above state, the tool body 11 is rotated around the axis, so that the cut portion of the work material W is scraped off by the outer peripheral blade 19 as shown in FIG. The finishing blade 17 cuts the machined surface cut by the outer peripheral blade 19 into a plane.

Here, the tip 10 of the present embodiment has a configuration in which the side surface 14 serving as the positive rake surface of the finishing blade 17 is shared as the rake surface of the outer peripheral blade 19, and therefore, as shown in FIG. The radial rake angle γ3 matches the inclination angle given to the finishing blade 17. On the other hand, in the conventional example described above, the radial rake angle of the outer peripheral blade is a large negative angle equal to or larger than the inclination angle of the finishing blade. Therefore, according to the tip 10 of the present embodiment, the finishing blade is viewed from the bottom of the tool. The radial rake angle of the outer peripheral blade 19 can be set to a negative angle in a smaller range than in the past while maintaining the same inclination angle of 17. Further, a positive axial rake angle is also given to the outer peripheral edge 19 in accordance with the chip rake angle γ1 of the arc rake face 15 serving as a rake face. Therefore, according to the tip 10 of the present embodiment, the sharpness of the outer peripheral blade 19 is improved, and the occurrence of chatter vibration is suppressed,
As a result, an extremely high quality finished surface can be obtained.

In this embodiment, notched surfaces 18 are formed at all corners C of the front flank 12 so that the outer peripheral edge 19 is
Since the chips are provided at the corners, there is no waste of chips and the cost is low. In this embodiment, one of the upper and lower surfaces opposed to each other in the thickness direction of the chip 10 is used as the mounting
In this case, the thickness of the tip 10 can be controlled in order to adjust the amount of protrusion of the finishing blade 17 toward the front end side in the tool axis direction (hereinafter referred to as a runout amount). However, the thickness control of the chip 10 largely depends on the grinding accuracy of the front flank 12 and the mounting surface 13, and the precision of the grinding is larger than that of the side flank 12 and the mounting surface 13 than the side surface 14 having a small area. Can be easily improved.
Therefore, according to this embodiment, it is possible to improve the processing accuracy by eliminating the variation in the amount of run-out due to the poor accuracy of the chip 10.

[0018]

As described above, the chip according to the present invention is provided at the corner portion of the front flank which is located at one end of the finishing blade in plan view from a direction orthogonal to the front flank. A notch surface that intersects one end of the finishing blade at an obtuse angle is formed, and an outer peripheral blade is formed at an intersection ridge line between the notch surface and the positive rake surface for the finishing blade. Can be set to a negative angle in a smaller range than before, and the axial rake angle can also be made positive. Therefore, the sharpness of the outer peripheral edge is improved, chatter vibration is suppressed, and as a result, an excellent effect that a high-quality finished surface can be obtained is achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a chip according to an embodiment of the present invention.

FIG. 2 is a side view of a chip.

FIG. 3 is an arrow view from a direction III in FIG. 2;

FIG. 4 is a view from arrow IV in FIG. 3;

FIG. 5 is a view as seen from a direction V in FIG. 3;

FIG. 6 is an axial sectional view of a tool main body on which the tip shown in FIG. 1 is mounted.

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

FIG. 8 is a plan view showing a state where the tip shown in FIG. 1 is mounted on a tool main body.

FIG. 9 is a view as viewed from the direction IX in FIG. 8;

FIG. 10 is a plan view of a conventional chip.

FIG. 11 is a view as seen from the direction XI in FIG. 10;

FIG. 12 is a view showing a state in which the tip shown in FIG. 10 is mounted on a tool main body.

13 is a view as viewed from the direction of the arrow XIII in FIG. 12;

[Explanation of symbols]

 Reference Signs List 10 insert 11 tool body 12 front flank 13 mounting surface 14 side surface 15 arc rake surface 16 flat rake surface 17 finishing blade 18 notch surface 19 outer peripheral blade

Claims (4)

(57) [Claims] 1. One side of an upper and lower surface, which is a polygonal flat plate and faces in the thickness direction, is a front flank, and the other is a mounting surface to a tool body. At least one of which is a positive rake surface inclined in a direction intersecting the front flank at an acute angle, and a throwaway tip having a finishing blade formed at an intersection ridge portion between the positive rake surface and the front flank; In the corner portion of the front flank, a corner portion located on one end side of the finishing blade, a notched surface intersecting at an obtuse angle with one end portion of the finishing blade in a plan view from a direction orthogonal to the front flank surface. Wherein a peripheral edge is formed at an intersection ridge line between the notched surface and the positive rake surface for the finishing blade. 2. The indexable insert according to claim 1, wherein the cutout surface and the outer peripheral edge are formed at all corners of the front flank. 3. The method according to claim 1, wherein a width occupied by the outer peripheral edge in a direction orthogonal to the front flank is set in a range of 0.2 mm to 1.0 mm. Indexable tip. 4. The indexable insert according to claim 1, wherein the finishing blade is formed in a convex curve shape.