JP2519796Y2 - Throw-away tip - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throw-away tip removably attached to a tool body of a cutting tool, and more particularly to a throw-away tip having a high processing ability for chips generated at a nose portion of a cutting blade. .

[0002]

2. Description of the Related Art In recent years, as a throw-away tip (hereinafter referred to as "tip"), which has an improved processing ability of chips generated in the nose portion of a cutting edge, a breaker is provided on a rake face connected to the nose portion of the cutting edge. What is formed is actively provided. In addition, as a mode of providing such a breaker, there are an example in which a ridge breaker extending in a direction that divides the nose portion of the cutting edge into two substantially equal parts and an example in which an island-shaped breaker is independently provided near the nose part There are two types.

16 to 22 are views showing an example of a chip provided with a ridge breaker of the above-described two types of breakers. In these figures, 1 is a chip, 2 is a chip 1
The rake face 3 is a flank face of the tip 1, and a cutting edge 5 having a nose portion 4 is formed at an intersection ridge line between the rake face 2 and the flank face 3. A ridge breaker 6 is formed on the rake face 2 and extends in a direction that divides the nose portion 4 of the cutting edge 5 into two equal parts. The tip of the ridge breaker 6 is flat when viewed from the side facing the rake face 2. It is formed on a convex curved surface 7 protruding toward the apex P of the nose portion 4. As is apparent from the contour lines h _{1 to} h ₄ drawn with the upper surface 6a of the ridge breaker 6 as a reference, the convex curved surface 7 decreases in radius of curvature from the rake surface 2 toward the upper surface 6a of the ridge breaker 6. Is formed. Moreover, the centers of curvature O _{1 to} O ₄ of the contour lines h ₁ to h ₄ passing on the convex curved surface 7 are arranged on one straight line L orthogonal to the upper surface 6 a of the ridge breaker 6, whereby the convex curved surface 7 is formed. It forms part of the conical surface. The chip 1 in which the convex curved surface 7 forming a part of the conical surface is provided at the tip of the ridge breaker 6 as described above is hereinafter referred to as a first conventional example. Then, as the chips belonging to the first conventional example as described above, Japanese Utility Model Publication No. 59-191201 and Japanese Utility Model Publication No. 5
The one described in 6-2302 is known.

On the other hand, the chip 10 shown in FIGS.
Is formed by forming an island-shaped breaker 11 projecting from the rake face 2 on the rake face 2 in the vicinity of the nose portion 4. The island-shaped breaker 11 of this example is apparent from the contour lines h _{1 to} h _4. Thus, it is formed so as to form a part of the spherical surface. Chip 10 having such an island breaker 11
Is hereinafter referred to as a second conventional example. Then, as a chip belonging to the second conventional example, there is an actual Japanese Utility Model Publication No. 52-93984.
No., Jitsukaihei 2-104904, Jitsukai 54-3899
The one described in No. 7 is known.

The chip 20 shown in FIGS.
In the same manner as the first conventional example, a ridge breaker 21 extending in a direction that bisects the nose portion 4 is formed on the rake face 2, but the tip shape of the ridge breaker 21 is different.
That is, in the first conventional example, the convex curved surface 7 at the tip of the ridge breaker 6 projects in an arc shape toward the apex P of the nose portion 4 in a plan view from the side facing the rake face 2, In the tip 20 of this example, the convex curved surface 22 formed at the tip of the ridge breaker 21 has a cross section view orthogonal to the extending direction of the ridge breaker 21 as shown in FIGS. 34 to 36.
Is formed so as to project upward in an arc shape. The radius of curvature of the convex curved surface 22 on the cross section is reduced toward the apex P of the nose portion 4, whereby the upper edge line 22a of the convex curved surface 22 (see FIGS. 29 and 30).
It gradually falls toward the rake face 2. The chip 20 having such a ridge breaker 21 is hereinafter referred to as a third conventional example.

[0006]

The chips of the first to third conventional examples described above still have room for improvement in chip disposal performance. That is, in the chip 1 shown in the first conventional example, as is clear by comparing FIGS. 17, 24 and 30, the rising of the tip (convex curved surface 7) of the ridge breaker 5 is higher than in other conventional examples. Because it's steep,
If the cutting speed and depth of cut are increased, clogging of chips is likely to occur. In order to prevent this chip clogging, it is necessary to keep the entire convex curved surface 7 of the ridge breaker 5 away from the nose portion 4, but in this case, chips do not collide with the breaker in a region where the cutting speed and the cutting depth are minute. However, there arises an inconvenience that the desired chip disposal performance cannot be obtained.

On the other hand, in the second conventional example, since the breaker rises gently, chip clogging is less likely to occur even when the tip of the breaker 11 approaches the nose portion 4, and a relatively wide range. With this, good chip disposal performance can be exhibited. In addition, by changing the position of the island-shaped breaker 11 or providing a plurality of island-shaped breakers 11, the range in which smooth chip disposal can be performed can be further expanded. However, in the second conventional example, the volume of the island-shaped breaker 11 is much smaller than that in the first conventional example, and since the island-shaped breaker 11 is isolated on the rake face 2, the island-shaped breaker 11 is scraped by scraping with chips. However, there is an inconvenience that the wear of the steel advances rapidly.

Also in the third conventional example, although the convex curved surface 22 at the tip of the breaker rises gently, chip clogging is less likely to occur, but the ratio of the convex curved surface 22 to the total length of the projected line breaker 21 is large, and the breaker volume is large. Is smaller on the tip side than the first conventional example, so that the breaker wear progresses earlier as in the second conventional example. The present invention has been made under such a background, and an object thereof is to provide a chip that has a wide range in which smooth chip disposal can be performed and that can prevent early wear of a breaker.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention has a cutting edge having at least one nose portion formed at the ridge line intersecting with a rake face and a flank face. A throw-away tip in which a ridge breaker extending in a direction that divides the nose part into approximately two equal parts is formed on a rake face that is continuous with the nose part, the ridge breaker having a tip facing the rake face. Has a convex curved surface projecting toward the apex of the nose portion of the cutting edge when viewed in plan from the side, the convex curved surface has a radius of curvature of a contour line passing on the convex curved surface from the rake surface. It is formed such that it gradually decreases toward the upper end of the ridge breaker, and the center of curvature of the contour line gradually separates from the apex of the nose portion of the cutting edge toward the upper end of the ridge breaker. Tena It is intended.

[0010]

According to the above construction, since the tip of the ridge breaker is formed by the convex curved surface which projects toward the apex of the nose of the cutting edge when viewed in plan from the side facing the rake face, the ridge breaker is formed. The volume of the tip of the breaker is sufficiently secured as in the first conventional example described above, and early wear is prevented. Moreover, the radius of curvature of the convex curved surface decreases toward the upper end of the ridge breaker, and the center of curvature recedes from the apex of the nose toward the upper end of the ridge breaker, so the tip of the breaker rises gently. As a result, chip clogging does not occur even if the cutting speed and depth of cut increase.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. First, a schematic configuration of a chip according to this embodiment will be described with reference to FIGS. As shown in these drawings, the tip 30 according to the present embodiment is formed by molding a hard material such as cermet or cemented carbide into a flat plate shape having a substantially parallelogram shape in a plan view. A pair of upper and lower surfaces 31, 32, four peripheral surfaces 33 arranged around the upper and lower surfaces 31, 32, and the center of the upper and lower surfaces 31, 32 penetrating the chip 30 in the thickness direction. And a mounting hole 34 that opens.

The upper surface 31 is provided around the mounting hole 34 and is a flat boss surface 35 extending in a direction orthogonal to the axis of the mounting hole 34, and a rake surface 36 which is lowered from the boss surface 35 by one step.
And a cutting edge 38 having a corner portion 37 that is curved with a desired radius of curvature is formed at the ridge line portion where the rake face 36 and the peripheral surface 33 intersect. Therefore, in this example, the peripheral surface 33
Will form the flank. The peripheral surface 33 is formed on a plane orthogonal to the boss surface 35 of the upper surface 31, whereby the chip 30 has a so-called negative shape. Although the upper surface 31 has been described above, the lower surface 32 is also formed in the same shape and size as the upper surface 31. Therefore, in the following, the description of the upper surface 31 is also applied to the lower surface 32 as it is.

A ridge breaker 39 extending in a direction that divides the nose portion 37 into approximately two equal parts is formed on the rake face 36 which is continuous with the nose portion 37 of the cutting edge 38. The rear end side of the ridge breaker 39 is connected to the boss surface 35 via a first widened portion 40 that bulges toward the rear end portion 37a of the nose portion 37. Then, the upper surfaces 40a of the first widened portions 40
The upper surface 39a of the ridge breaker 39 is formed as a flat surface flush with the boss surface 35. The first widened portion 4
0 provides a barrier 40b for curling chips generated at the rear end portion 37a of the cutting edge 37, and the upper surface 3
It is provided to increase the seating area when 1 is used as a seating surface for a tool holder (not shown) and to enhance the stability of the tip. From the viewpoint of increasing the seating area,
The boss surface 35 has a protruding portion 41 protruding toward the center of each side of the upper surface 31, and in the vicinity of the obtuse angle end C ₂ of the chip 30, it is slightly smaller than the first widened portion 40 or the protruding breaker 39. The second widened portion 42 and the ridge portion 43 are formed, and the upper surfaces 42a and 43a thereof are formed as flat surfaces that are flush with the boss surface 35.

The rake face 3 is provided on the side of the ridge breaker 39.
6, side walls 44 are formed that stand up from the ridge breaker 39 to the upper surface 39a of the ridge breaker 39.
From the top to the upper surface 39a, an inclined surface is formed that recedes toward the widthwise center of the ridge breaker 39. A convex curved surface 45 that projects toward the apex P of the nose portion 37 when viewed in plan from the side facing the rake face 36 is formed at the tip of the ridge breaker 39.

As shown in FIGS. 6 to 14, the convex curved surface 45
Is four contour lines h ₁ of to h passes over convex surface 45 of the contour lines h ₁ to h ₅ depicting a boss surface 35 as a reference ₄ (contour h ₁ is equal to the circumference of the upper surface 39.) Curvature Radius is
It gradually decreases from the rake face 36 toward the upper surface 39a of the ridge breaker 39, and the centers of curvature O _{1 to} O _{4 of} the contour lines h _{1 to} h ₄ move toward the upper surface 39a of the ridge breaker 39. It is formed so as to be gradually separated from the apex P of the portion 37. Here, the specific shape such as the radius of curvature and the center of curvature of the convex curved surface 45 is appropriately determined according to the cutting conditions in which the tip 30 is used, the material of the work material, etc., but the radius of curvature of the nose portion 37 is Nose portion 37 when R ₀
From the apex P to the tip of the ridge breaker 39 is 0.4R _{0 to} 2.0R ₀ , and the convex curved surface 45 is attached to the chip 3
The inclination angle θ (see FIG. 7) of the ridge line K with respect to the boss surface 35 is 12 ° to 22 ° when viewed in a cross section in a direction orthogonal to the boss surface 35 along a diagonal line connecting the acute-angled ends C _{1 of} 0. The shape should be determined so that By the way, in the illustrated example, the radius of curvature R ₀ of the nose portion 37 is 0.8 mm and the distance M is
Is set to 0.5 mm and the tilt angle θ is set to 15 °. The ridgeline K of the convex curved surface 45 does not necessarily have to be formed as a straight line, and may be a convex curve or a concave curve. The preferable range of the inclination of the ridgeline K in the case of forming these curved lines is that the inclination angle of the tangent line at each part of the ridgeline K is within the range of the inclination angle θ.

As shown in FIGS. 1 to 5, a first land portion 46 orthogonal to the peripheral surface 33 is formed between the nose portion 37 and the rake face 36. Further, the portion sandwiched between the first widened portion 40 and the second widened portion 42 has the first
A second land portion 47 having a width wider than that of the land portion 46 is formed, and an auxiliary blade portion 48 is formed at an intersecting ridgeline between the second land portion 47 and the peripheral surface 33. This auxiliary blade 4
Numeral 8 is provided in order to increase the economical efficiency of the tip by performing other processing such as chamfering with a high load on the same tip after the corner portion 37 of the cutting edge 38 is used up. The cutting edge 38 of the present embodiment is configured by the corner portion 37 and the corner portion 37.

In the tip 30 constructed as described above, the convex curved surface 45 protruding toward the apex P of the nose portion 37 when the tip of the ridge breaker 39 is viewed in plan from the side facing the rake face 36. Since it is formed by, the volume of the tip portion of the ridge breaker 39 is sufficiently secured as in the first conventional example, and early wear is prevented. In addition, the radius of curvature of the convex curved surface 45 decreases toward the upper surface 39a of the ridge breaker 39, and the center of curvature of the convex curved surface 45 becomes the upper surface 3a.
9a, the nose portion 37 recedes from the apex P of the nose portion 37. Therefore, the leading edge of the ridge breaker 39 gently rises, that is, the inclination of the ridge line K shown in FIG. 7 becomes gentle. Therefore, the upper tip of the ridge breaker 39 is located at the nose portion 3.
7 is sufficiently retracted, so that chip clogging is less likely to occur even if the cutting speed or the cutting depth is increased. On the other hand, since the lower part of the tip of the ridge breaker 39 is sufficiently close to the nose portion 37, the chips are reliably restrained by the ridge breaker 39 and the division of the chips is promoted even if the cutting speed and the depth of cut are small.
Therefore, according to the tip 30 of the present embodiment, good chip disposal performance can be exhibited in a wide range.

In this embodiment, the cutting blade 38 is provided with the auxiliary blade portion 48, but the present invention is not limited to this. For example, as shown in FIG.
The nose portion 37 may be provided by enlarging it to the ridge line intersecting with 3. Further, the shapes of the upper and lower surfaces 31 and 32 are not limited to the parallelogram shape, and may be variously modified such as a square shape and a rhombus shape other than the triangular shape shown in FIG. Further, the tip is not limited to the negative shape, and a positive shape in which the peripheral surface 33 inclines so as to form an acute angle with the boss surface 35 is naturally applicable.

[0019]

As described above, according to the present invention, the volume of the tip portion of the ridge breaker is sufficiently secured as in the first conventional example to prevent early wear, and the tip of the ridge breaker is prevented. Since the rising speed of the blade becomes slower, chip clogging is less likely to occur even if the cutting speed and cutting depth increase, and the lower tip of the ridge breaker is sufficiently close to the nose part of the cutting edge to reduce cutting speed and cutting depth. Since chips are reliably restrained even if the number of chips is reduced, it is possible to provide a chip in which the range in which smooth chip processing can be performed is wide, and in which early wear of the breaker can be prevented.

[Brief description of drawings]

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

FIG. 2 is a side view of the chip shown in FIG. 1 taken along arrow II in FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

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

FIG. 5 is a sectional view taken along line VV in FIG. 1;

FIG. 6 is an enlarged view of the vicinity of the nose portion of the cutting edge of the tip shown in FIG.

7 is a sectional view taken along line VII-VII in FIG.

8 is a sectional view taken along line VIII-VIII in FIG.

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

10 is a cross-sectional view taken along line XX of FIG.

11 is a sectional view taken along line XI-XI of FIG.

12 is a sectional view taken along line XII-XII in FIG.

13 is a sectional view taken along line XIII-XIII in FIG.

14 is a sectional view taken along line XIV-XIV in FIG.

FIG. 15 is a plan view of a chip according to another embodiment of the present invention.

FIG. 16 is an enlarged view of the vicinity of the cutting edge nose portion of the tip according to the first conventional example.

17 is a sectional view taken along line XVII-XVII in FIG.

18 is a sectional view taken along line XVIII-XVIII in FIG.

19 is a sectional view taken along line XVI-XVI in FIG.

20 is a sectional view taken along line XX-XX in FIG.

21 is a cross-sectional view taken along line XXI-XXI of FIG.

22 is a sectional view taken along line XXII-XXII in FIG.

FIG. 23 is an enlarged view of the vicinity of a cutting edge nose portion of a tip according to a second conventional example.

24 is a sectional view taken along line XXIV-XXIV in FIG.

25 is a sectional view taken along line XXV-XXV in FIG.

FIG. 26 is a sectional view taken along line XXVI-XXVI in FIG.

27 is a sectional view taken along line XXVII-XXVII in FIG.

28 is a sectional view taken along line XXVIII-XXVIII in FIG.

FIG. 29 is an enlarged view of the vicinity of a cutting edge nose portion of a tip according to a third conventional example.

30 is a sectional view taken along the line XXX-XXX of FIG. 29.

31 is a cross-sectional view taken along the line XXXI-XXXI in FIG. 29.

32 is a sectional view taken along the line XXXII-XXXII in FIG. 29.

FIG. 33 is a sectional view taken along the line XXXIII-XXXIII in FIG. 29.

34 is a cross-sectional view taken along the line XXXIV-XXXIV in FIG. 29.

35 is a sectional view taken along the line XXXV-XXXV in FIG.

36 is a sectional view taken along the line XXXVI-XXXVI in FIG. 29.

[Explanation of symbols]

30 Chip 33 peripheral surface (flank) 36 rake face 37 nose portion 38 cutting edge 39 projecting breaker 45 convex curved h ₁ to h ₄ contour O ₁ ~ O ₄ vertices of the center of curvature P nose contour

Claims (1)

(57) [Scope of utility model registration request] 1. A cutting edge having at least one nose portion is formed at an intersecting ridge line portion of a rake face and a flank face, and the nose portion is almost equal to 2 etc. on the rake face continuous with the nose portion of the cutting blade. A throw-away tip formed by forming a ridge breaker extending in a dividing direction, wherein the ridge breaker has a tip end of the nose portion of the cutting edge when viewed in plan from a side facing the rake face. Has a convex curved surface protruding toward the apex of the convex curved surface, the radius of curvature of the contour line passing on the convex curved surface gradually decreases from the rake face to the upper end of the ridge breaker, and, A throw-away tip formed so that the center of curvature of the contour line is gradually separated from the apex of the nose portion of the cutting edge toward the upper end of the protruding line breaker.