JPH088009Y2 - Throw-away tip for face milling - Google Patents

Description

[Detailed Description of the Invention] (Industrial field of application) The present invention relates to a throw-away tip for face milling, and in particular, the cutting edge shape of a high rake blade die is improved to be suitable for cutting steel. is there.

(Prior Art) Conventionally, a rolling tool having a large regular rake angle in the axial direction and a convex curved rake face is disclosed in, for example, Japanese Patent Laid-Open No. 62-65109.
It is disclosed in Japanese Patent Publication No.

(Problems to be solved by the invention) However, in the one disclosed in the above-mentioned publication, since the entire main cutting edge is formed of a curved surface, the axial rake angle gradually increases as the cutting depth increases. Therefore, at a low cutting depth, there is a problem that the rake angle is small and the cutting resistance is large, and the strength of the tip of the cutting edge is accordingly reduced.

(Means for ameliorating the problems) The present invention has been made in view of the above points, and is a throw-away tip for a face milling machine made of a substantially parallelogram plate or a substantially diamond plate having an acute diagonal corner. ,
This is an improvement in the blade edge configuration of the inclined side surface that constitutes the rake face.

That is, at the cutting end of the inclined side surface of the throw-away tip, an arcuate surface that rounds the apex portion that is an acute angle or a multi-step surface that goes toward an obtuse angle is added, and the inclination angle by these arcuate surfaces or multi-step surfaces β, β ₁ , β ₂
Is smaller than the inclination angle α of the inclined side surface to enhance the edge strength.

(Function) The throw-away tip for face milling in the present invention forms a regular angle with a large axial rake angle when assembled in the cutter body, so that it can be cut with low cutting resistance and less vibration. Is.

Further, by adding an arcuate surface or a plurality of step surfaces to the cutting edge forming an acute angle, the tip strength of the cutting edge is enhanced. In this case, since the inclination angle of the arcuate surface or the plurality of stepped surfaces is small, the cutting edge at the tip is further strengthened.

(Embodiment) An embodiment of a throw-away tip for face milling of the present invention will be described below with reference to the drawings.

In FIG. 1 to FIG. 3, (1) is a throw-away tip for a face milling machine having a substantially parallelogram plate shape having sharp diagonal corners, and is directed from the upper surface (2) to the lower surface (3). And a central mounting hole (4) is drilled. In this case, the apex angle forming the acute angle of the diagonal corner is usually A = 55 ° to 70 °.

Then, the throw-away tip (1) is formed as an inclined side surface (5) in which one of the opposite side surfaces has an inclination angle α. Therefore, the upper surface (2) of the throw-away tip (1) downsizes the lower surface (3) due to the existence of the inclination angle α. Further, the other facing side surface becomes a vertical side surface (6) on the lower surface (3) side, and inclined step surfaces (7) and (8) are formed at intersections with the upper surface (2). When the throw-away tip (1) is incorporated into the tip seat (21) of the cutter body (20), the inclined step surfaces (7), (8) and the upper surface (2) are inclined side surfaces (5). The front cutting edge ridge (9a), the sub cutting edge ridge (9b) and the main sub cutting edge (9c) are respectively formed by the ridge intersecting with.

Then, this throw-away tip (1)
As shown in FIGS. (A) to (c), the apex angle portion of the inclined side surface (5) is rounded by an arcuate surface (10) having a radius R. And
In this case, the inclination angle β by the arcuate surface (10) is set smaller than the inclination angle α of the inclined side surface (5) to further strengthen the cutting edge. The inclination angles α and β are normally α = 10 ° to 25 °, β =
It is set within the range of 5 ° to 20 °.

The throw-away tip (1) of the present invention thus constructed is fixed in the tip seat (21) of the cutter body (20) by, for example, the tightening screw (22) as described above. Regarding the blade edge angle, the rake angle in the axial direction is AR = 15 ° to 25 ° when the straight cutting edge is used as a reference.
The radial rake angle is RR = -25 ° to -35 °, and the corner angle is CA = 25 ° to 45 °.

Further, FIGS. 8 (a) to 8 (d) show a modification of the throw-away tip (1) of the present invention, in which a plurality of step surfaces (11) ( 1
2). And a plurality of steps (11) (12)
Is changed from an acute angle to an obtuse angle, and has a relationship of A ₁ <A ₂ <A ₃ in terms of apex angle. In this case, the apex angle A ₁ is A ₁ = 55 ° to 70 as described above.
Set within the range of °, for A ₂ and A ₃ , A ₂ = 60 °
To 75 °, it is set within the range of A ₃ = 70 ° ~85 °. Also,
Regarding the inclination angles β ₁ and β ₂ of the multi-step surfaces (11) and (12),
When β ₁ > β, β ₁ is set within the range of 5 ° to 22 ° and β ₂ = 0 ° to 20 °.

FIG. 9 shows the life results when the present invention and the conventional product are incorporated into the cutter body (20) and cut.
In this case, the product of the present invention is shown in FIGS. 1 to 4 (a) (b).
With the basic shape shown in (c), A = 19.05 mm,
b = 12.78 mm, c = 4.76 mm, apex angle A = 58 °, inclination angle α = 20
Set 0 ° and β = 12 °, and set 0 along each cutting edge.
17mm angle honing (-25 °) is applied.
On the other hand, the conventional product basically has the same shape as the product of the present invention, and the inclined side surface (5) has a convex curved surface as seen in the above-mentioned JP-A-62-65109. They differ in points.

In the cutting test, the device of the present invention and the conventional product were assembled into the cutter body (20) shown in Figs. 5 to 7 so that the blade diameter was 160mm, and the hole diameter was 100m x 200mm. About Work Material (SCM40 H _B 260 ~ 280)
This is one-flute cutting. The cutting conditions at this time were a cutting speed V = 116 m / min, a feed S _Z = 0.28 mm / blade, and a cutting depth d = 4.0 mm.

As a result, the product of the present invention had a service life of about 55 minutes as apparent from FIG. 9, while the service life of the conventional product was about 46 minutes.
The product of the present invention was excellent. The cutting life was a high rake blade type and had a curved edge defect. Further, the throw-away tip (1) shown in FIGS. 8 (a) to (d).
A similar fracture resistance test was conducted on the above, but almost the same results were obtained.

(Effect of the Invention) As described above, the present invention has an arcuate surface (10) or a plurality of stepped surfaces (11) at the acute angle end of the inclined side surface that constitutes the rake surface.
(12) is added and the inclination angles β, β ₁ , β ₂ thereof are made smaller than the inclination angle α of the inclined side surface (5). Therefore, the cutting edge of the cutting edge is strengthened, and the fracture resistance is excellent and a long life can be expected. Further, the high rake blade type reduces the cutting resistance and suppresses the vibration, thus improving the workability.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a throw-away tip for a front milling cutter of the present invention, FIG. 2 is a side view thereof, FIG. 3 is a bottom view, and FIG. 4 (a) is a cutting edge portion. FIG. 4 (b) is a partial bottom view from the diagonal left direction, FIG. 4 (c) is a partial bottom view from the diagonal right direction, and FIGS. FIG. 5 is a view when the throw-away tip for face milling of the present invention is assembled in the cutter body, FIG. 5 is a partial front view of the face milling, and FIG. 6 is
A sectional view and FIG. 7 are partial plan views and FIGS. 8A to 8D.
FIG. 8 is a view showing a modified example of the throw-away tip for face milling of the present invention, FIG. 8 (a) is a partially enlarged front view showing a cutting edge portion, and FIGS. 8 (b) to (d) are respectively FIG. 9 is a partial bottom view from the diagonal left direction, and FIG. 9 is a characteristic diagram showing the results of the defective lives of the product of the present invention and the conventional product. (1) …… Throw-away tip for face milling (2) …… Upper surface, (3) …… Lower surface (4) …… Center mounting hole, (5) …… Inclined side surface (6) …… Vertical side surface, ( 7) (8) …… Inclined step surface (9a) …… Front cutting edge, (9b) …… Sub cutting edge (9c) …… Main and sub cutting edge, (10) …… Arc surface (11) (12) …… Multiple steps

Claims (1)

[Scope of utility model registration request] 1. A substantially parallelogram plate or a substantially rhombic plate having a central mounting hole (4), and one opposing side surface of the plate is miniaturized from an upper surface (2) to a lower surface (3). Are formed as inclined side surfaces (5) each having an inclination angle α, and the other opposite side surface is a vertical side surface (6) on the lower surface (3) side, and an inclined step surface is formed at the intersection with the upper surface (2). (7) and (8) are further provided, and the diagonal corners having a pair of acute angles form the cutting edge and intersect the inclined side surface (5) with the inclined step surfaces (7) (8) and the upper surface ( In the throw-away tip for face milling, wherein the front cutting edge ridge (9a), the sub cutting edge ridge (9b) and the main sub cutting edge ridge (9c) are respectively formed between the two, the inclined side surface (5) On the cutting edge side of, the arc-shaped surface (10) that rounds the apex angle that constitutes an acute angle or A plurality of step surfaces (11) (12) facing the corner are added, and the inclination angles β, β1, β2 formed by the arcuate surface (10) or the plurality of step surfaces (11) (12) are inclined side surfaces ( Inclination angle α of 5)
Throw-away tip for face milling that is smaller than.