JPH031139Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a throw-away tip that is detachably attached to the outer periphery of a tool body such as a side cutter or an end mill.

[Prior Art] In various indexable cutting tools such as end mills, face mills, and side cutters, a plate-shaped indexable tip (hereinafter referred to as ) is removably attached.

17 to 19 show an example of a conventional chip of this type.

In FIGS. 17 to 19, this chip 1 has a parallelogram-like appearance with upper and lower surfaces 2 and 3 parallel to each other, and the lower surface 3 is used as a seating surface.
Main cutting edges 4, 4 are formed on the ridge portion of the long side of the upper surface 2. Then, in a predetermined width portion of the upper surface 2 along the main cutting edge 4, a lower surface 3 is gradually formed from the center side of the upper surface 2 toward the main cutting edge 4 at an angle shown by β in FIG. A chamfer surface 5 is formed which slopes to the side. In addition, the side surface 6 from the main cutting edge 4 of the chip 1 to the lower surface 3 is directed from the main cutting edge 4 to the lower surface 3 at an angle shown by α in the figure.
It is formed by an inclined surface that slopes toward the center of the Note that the reference numeral 7 in the figure indicates a mounting hole for the throw-away tip 1.

As shown in FIGS. 20 and 21, the conventional tip 1 having the above shape has its lower surface 3, which serves as a seating surface, in contact with the tip mounting surface 9 of a tool body 8 such as a cutter. In addition, its mounting hole 7
By tightening the clamp screw 10 inserted therein, the tool body 8 is removably attached to the tool body 8 and ready for use. Here, the above chip 1 is
A positive axial rake angle A and a positive radial rake angle are set so that the chimney face 5 and the upper surface 2, which are the outer peripheral flanks, are located inside the rotation locus Y of the main cutting edge 4 about the axis X of the tool body 8, respectively. It is attached with an R. Incidentally, the above radial rake angle R is defined as the angle between the line connecting the axis X and the main cutting edge 4 and the line passing through the axis X and perpendicular to the upper and lower surfaces 2 and 3 of the chip ₁ . _R1 −α)
is the angle represented by .

[Problems to be solved by the invention] By the way, in general, in the case of such a chip 1, the tool body 8 has its axial rake angle A.
By increasing both the radial rake angle R and the radial rake angle R in the positive direction, the cutting resistance and the generation of cutting heat are further reduced, making it possible to perform cutting with even higher efficiency.

However, in the conventional chip 1 described above, as shown in FIG. 19, the main cutting edge 4 and the upper surface 2 are each parallel to the lower surface 3, so as shown in FIGS. As such, if an attempt is made to increase the axial rake angle A, the length H of the tip 1 in the outer peripheral direction of the tool body 1, which must be positioned within the rotation locus Y described above, becomes long. In other words, in order to position the chamfer surfaces 5, 5 and the upper surface 2 of this chip 1 inside the rotation locus Y, the angle indicated by _R1 described above inevitably becomes large, so that R= In order to further make the radial rake angle R positive according to the relationship α−R ₁ , the inclination angle α of the side surface 6 must also be adjusted to the above angle.
It must be made larger in advance in proportion to the amount of increase in _R1 . As a result, the angle of the cutting edge becomes smaller, which reduces the strength of the cutting edge and causes chipping and chipping, and further deteriorates seating rigidity, leading to a reduction in cutting load resistance. .

[Purpose of the invention] This invention was made in view of the above circumstances.
To provide a throw-away tip that can be mounted on a tool body with large axial rake angles and radial rake angles without deteriorating cutting edge strength or seating rigidity, and can thus perform highly efficient cutting. The purpose is to

[Means for Solving the Problems] The chip of this invention has a rectangular plate shape with a seating surface formed on the lower surface, and a main cutting edge is formed on the ridge of the upper surface. A diagonal line connecting the pair of corner portions is defined as a ridgeline on the upper surface, and a flat inclined surface gradually approaches the lower surface side as it goes from the diagonal line to the other corner portions.

[Example] Figures 1 to 10 show an example of the chip of this invention.

In FIGS. 1 to 3, this chip 11 is a plate-shaped member with an approximately diamond-shaped appearance, and its lower surface 12 is used as a seating surface, and the ridge of its upper surface 13 has a
Main cutting edges 14, 14 are formed respectively. The thickness of the upper surface 13 between the upper and lower surfaces 12 and 13 gradually decreases from the diagonal line M connecting the obtuse corner portions 15 and 15 of the upper surface 13 toward the acute angle corner portions 16 and 16, respectively. As a result, it is formed by flat inclined surfaces 17, 17 which are inclined at an angle δ with respect to a plane parallel to the lower surface 12. Note that the reference numeral 18 in the figure indicates a mounting hole for the throw-away tip 11.

As shown in FIGS. 4 to 7, such chips 11 include a large number of chips formed as appropriate in a spiral shape along the axial direction, for example, at four locations on the outer periphery of the tool body 19. Chip mounting seat 20...
They are detachably attached to each other via clamp screws 21 for use. Here, as shown in FIGS. 6 and 7, these chips 11... are attached to the tool body 19 at their respective acute corner portions.
6... are located on the forward end side of the tool body 19 in the direction of rotation, and are attached with positive axial rake angles A and radial rake angles R, respectively, as in the conventional tool.

However, for such chip 11,
The upper surface 13, which becomes the outer circumferential relief surface when installed,
A diagonal line connecting the obtuse corner parts 15, 15 of the upper surface 13 is defined as a ridge line, and flat inclined surfaces 17, 17 gradually approach the lower surface 12 as they move from this diagonal line to the acute angle corner parts 16, 16. Therefore, as shown in Fig. 6, if the diagonal line portion where the chip thickness is maximum is located within the rotational trajectory Y when the chip is mounted on the tool, There is no need to consider this part. Therefore, the tool outer circumferential direction length H1 of the chip 11 to be located within the rotational trajectory Y
However, the length of the tip 11 is reduced by half, and the effect of halving the length H1 is exerted regardless of the size of the axial rake angle A. Therefore, as shown in FIGS. 8 and 9, even when the axial rake angle A is increased, a line connecting the axis X and the main cutting edge 14 passes through the axis X of the tool body 19 and the lower surface thereof. The amount of change in R ₂ of the angle formed by the line perpendicular to 12 can be kept extremely small. Therefore, there is no need to increase the angle of inclination of the side surface 22, and highly efficient cutting can be performed without deteriorating the strength of the cutting edge or seating rigidity. In addition, in the chip 11 of this embodiment, since the inclined surface 17 is made flat, the inclination angle δ (see FIG. 3) of the inclined surface 17, which serves as the outer peripheral flank for the main cutting edge 14, is from the center of the chip to the inclined surface. It is maximum when measured in the direction toward the corner portion 16 located at the tip, and becomes smaller when measured in the direction intersecting the main cutting edge 4 from the center of the chip. Therefore, when the chip is attached to the tool, the clearance angle of the main cutting edge 14 in the circumferential direction of the tool increases as it approaches the corner part 15. Therefore, if the clearance angle is set based on the corner part 16, it can be adjusted to other parts. , a clearance angle greater than that is ensured, making it easy to set the clearance angle.

Furthermore, since the inclined surface 17 is flat, the main cutting edge 14 formed on its ridge also has a straight shape. As a result, plane machining can be performed with high precision, and the rotation radius of the main cutting edge 14 changes. The same chip can be used for all applications, making it highly versatile.

[Other Embodiments] Figures 10 to 12 show a second example of this invention, and parts common to those shown in Figures 1 to 3 are given the same reference numerals. The explanation will be omitted.

10 to 12, in the chip 25 of this example, the inclination angle α ₁ of the side surface 26 from the main cutting edge 14 to the lower surface 12 is larger than that shown in FIGS. 1 to 3. is formed. A diamond-shaped plate-shaped seating portion 28 is formed between the lower end 26a of the inclined side surface 26 and the lower surface 12, the opposing side surfaces 27 being parallel to each other.

Moreover, FIGS. 13 to 15 show a third example of this invention.

In Figures 13 to 15, this chip 30
is a plate-like object with an approximately parallelogram external appearance, and its lower surface 3
1 serves as a seating surface, and main cutting edges 33, 33 are formed on the ridges of the upper surface 32, respectively. The upper surface 32 has corner portions 35, each forming an obtuse angle from a diagonal line _M1 connecting the slightly acute corner portions 34, 34 of the upper surface 32, respectively.
It is formed by flat inclined surfaces 36, 36 in which the thickness between the upper and lower surfaces 31, 32 gradually decreases toward 35. Also, in this chip 30, the inclination angle of the side surface 37 from the main cutting edge 33 to the lower surface 31 is
It is formed to be larger than those shown in FIGS. 1 to 3. And this sloping side 3
A diamond-shaped plate-shaped seating portion 39 is formed between the lower end portion 37a of 7 and the lower surface 31. Opposing side surfaces 38, 38 are parallel to each other.

According to the chips 25 and 30 shown in the second and third examples above, in addition to being able to obtain the same effects as those shown in the first example above,
Furthermore, even if the angle of inclination of the slope forming the top surface of a small chip is increased, or the slope of the side surface is increased, the effect of securing a sufficient seating area can also be obtained. can.

In the above embodiments, the external appearance is rhombic and parallelogram-shaped, but the external appearance is not limited to this, and as long as the top surface is formed in the same shape as each of the above-mentioned chips. Other rectangular plate shapes such as rectangles and squares may also be used.

Furthermore, when the tip is attached to the tool body for use, it is not limited to the case where the same type of chips are used at the same time; for example, as shown in FIG. Throwaway tip 41 having a square appearance
..., and at the same time, the diamond-shaped tip 11 shown in the first example is attached to the tip mounting seat at a position where front clearance is required for the main cutting edge on the tip side of the tool body 40. It may be used as a raw material.

[Effects of the invention] As explained above, the tip of this invention has a rectangular plate shape with a seating surface formed on the lower surface, and a main cutting edge is formed on the ridge of the upper surface. The tool body is formed by a diagonal line connecting the pair of corner parts of the upper surface as a ridge line, and a flat inclined surface that gradually approaches the lower surface side as it goes from the diagonal line to the other corner parts. When the chip is mounted on the main cutting edge, the length in the outer circumferential direction of the chip that should be positioned within the rotation locus of the main cutting edge can be substantially halved regardless of the size of the axial rake angle.

Therefore, according to this chip, the axial rake angle can be significantly increased to the positive side without deteriorating the strength of the cutting edge or seating rigidity, and the chip can be mounted on the tool body, allowing highly efficient cutting.

Furthermore, according to the chip of the present invention, since the inclined surface itself is a flat surface, when the tool is installed, if the clearance angle in the circumferential direction of the tool is set based on the corner located on the tip side of the inclined surface, the main It is possible to give the cutting edge a clearance angle larger than a predetermined clearance angle, and therefore the clearance angle can be easily set when the tool is attached.

Furthermore, since the main cutting edge formed on the ridge of the inclined surface is linear, it is possible to perform flat surface machining with high precision, and the same chip can be used even if the cutting blade rotation radius changes, increasing chip versatility. is also extremely high.

[Brief explanation of the drawing]

Figures 1 to 3 show a first embodiment of the throw-away chip of this invention. Figure 1 is a front view, Figure 2 is a view taken along line _A1 - _A1 of Figure 1, and Figure 3 is a view taken along line _A2 - _A2 in Figure 1, Figures 4 to 9 show an example of the state in which the above-mentioned tip is attached to the tool body, Figure 4 is a front view, and Figure 5 is a front view. is a bottom view, FIGS. 6 and 8 are enlarged views of section B in FIG. 5, respectively, FIGS. 7 and 9 are enlarged views of section C in FIG. 4, and FIGS. Fig. 10 is a front view, Fig. 11 is a view taken from line A ₃ - A ₃ in Fig. 10, and Fig. 12 is a view taken from line A ₄ - A ₄ in Fig. 10. 13 to 15 show a third embodiment of this invention, in which FIG. 13 is a front view, FIG. 14 is a view taken along line _A5 - _A5 in FIG.
5 is a view taken along line A ₆ - _{A 6} in FIG. 13, FIG. 16 is a front view showing another example of the chip of this invention attached to the tool body, and FIGS. 17 to 19 are views of the conventional chip. Fig. 17 is a front view, Fig. 18 is a view taken from line A ₇ - A ₇ in Fig. 17, and Fig. 19 is a view taken from line A ₈ - _{A 8} in Fig. 17. Figure 20~
Figure 23 shows the tip installed in the tool body, Figures 20 and 22 are bottom views showing the tip installed, and Figures 21 and 23 are front views of the same. be. 11, 25, 30, 41... Throwaway tip, 12, 31... Lower surface, 13, 32... Upper surface, 14, 33... Main cutting edge, 17, 36... Inclined surface, 15, 35... Obtuse angle corner part, 16, 34
...acute corner part, 22, 26, 27, 37,
38...Side surface, 28, 28...Seating portion, 20...
Chip mounting seat, 19, 40...Tool body, M,
M ₁ ...diagonal line, X...axis line, Y...rotation trajectory,
A...Axial rake angle, R...Radial rake angle.

Claims (1)

[Scope of utility model registration request] In a throw-away chip that has a rectangular plate shape with a seating surface formed on the lower surface and a main cutting edge formed on the ridge of the upper surface, the upper surface is defined as the diagonal line connecting the pair of corners of this upper surface as the ridge line. 1. A throw-away chip, characterized in that it is formed by flat sloped surfaces that gradually approach the lower surface side from the diagonal line toward the other corner portions.