JPH0750097Y2 - Throw-away tip used on turning broaches - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention mainly relates to a throwaway chip which is attached to a turning broach and used as a cutting blade.

[Prior Art] FIG. 8 shows a conventional throwaway chip (hereinafter referred to as a chip) of this type mounted on a turning broach.

In FIG. 8, the chip 1 is a plate-shaped plate made of cemented carbide or the like having a substantially rectangular outer shape, and mounting holes 4 are formed in the central portions of the upper and lower surfaces 2 and 3 thereof so as to penetrate therethrough. . Main cutting edges 6 are formed on the ridges of the side surfaces 5 located between the upper and lower surfaces 2 and 3 which are parallel to the axis of the mounting hole 4. One end of each side surface 5 is a rake face 7 of the main cutting edge 6, and the other end is a flank 8 of the adjacent main cutting edge 6. Side edges 9 are formed on the ridges of the upper and lower surfaces 2 and 3 on both sides of the rake face 7 and intersecting the main cutting edge 6.

As shown in FIG. 9, the conventional chip 1 having the above structure has a chip mounting seat 11 formed on a main body 10 of a turning broach, and a main cutting edge 6 of the chip mounting seat 11 protruding outwardly, so that a mounting hole 4 is formed.
It is detachably attached by a clamp bolt 12 inserted therein. Then, with respect to the work material W such as a crank shaft rotating in the direction of the arrow in the figure, the turning broach advances in one direction and the list amount in the radial direction of the cutting edge (0.5 mm to
(About 0.6 mm), the work material W is cut in the radial direction. Note that reference numeral 13 in the figure is a chip pocket for discharging chips in the main body 10.

[Problems to be Solved by the Invention] By the way, in the above-described conventional tip 1, when cutting the work material W, as shown in FIGS. 9 to 11, the upper and lower surfaces 2, 3 along the side blades 9, 9 are cut. Corner part (portion indicated by diagonal lines in Fig. 11)
Is rubbed by the side surface of the work piece W to be processed, and as a result, the life of the chip 1 is shortened.

Therefore, as shown in FIG. 12 and FIG.
Work piece W by attaching a lateral clearance angle δ to the upper and lower surfaces 2, 3
It is also possible to avoid interference with. However, in this case, since the widths of the adjacent main cutting edges 6 are inevitably narrowed and cannot be used as cutting edges, only the pair of main cutting edges 6 in the diagonal direction can be used. There was a problem of being uneconomical.

Further, as another cutting mode by the turning broach, there is a processing for simultaneously cutting the work W in both the axial direction and the radial direction as shown in FIGS. 14 to 16.
Also in this case, as in the case shown in FIGS. 9 and 10, in order to avoid the interference between the upper and lower surfaces 2 and 3 and the work material W, at least the lateral cutting edge angle δ ₂ is added. Therefore, it is necessary to add a lateral clearance angle δ ₁ to the lateral flank on the front side in the feeding direction.

However, if the chip 1 is cut as it is with the side clearance angle δ ₁ , so-called second hit occurs at the "B" portion of the upper surface 2 shown in FIG. 15, and normal cutting cannot be performed. There was a problem that it would end up.

The present invention aims to solve the above problems.

[Means for Solving the Problem] The throw-away tip used by being attached to the turning broach according to the present invention has a plate-like shape having a substantially rectangular appearance.
Mounting holes penetrating between these are formed in the central part of the upper and lower surfaces, and the ridge line portion parallel to the axis of the mounting holes on the side faces located between these upper and lower surfaces is the main cutting edge, and In a throwaway tip in which a side blade is formed on a ridge line where the rake face and the upper and lower faces of the blade intersect, the rake face of the main cutting edge is formed at both end portions of a pair of side faces that are not adjacent to each other, and At the ridge line portion where the pair of side surfaces and the upper and lower surfaces that are sandwiched between the side surfaces and are the front flanks of the main cutting edge intersect with each other,
A chamfer blade having a width dimension in the range of 0.5 mm to 1.5 mm over the entire length is formed, whereby a chamfer blade is formed between the main cutting edge and the side blade.

[Operation] In the chip having the above-described structure, when the front clearance angle is provided and the work material is radially cut in the same manner as in normal cutting, a clearance angle is formed in the chamfer. Further, when a lateral cutting edge angle and a lateral clearance angle are added in a process of simultaneously cutting the work material in the axial direction and the radial direction, the clearance angle is similarly formed in the chamfer. Therefore, in such a chip, the upper and lower surfaces of the chip are not rubbed by the processed side surface of the work material in any cutting process.

[Embodiment] FIG. 1 shows an example of the chip of the present invention.

In FIG. 1, the chip 21 is a plate-like member made of cemented carbide or the like having a substantially rectangular outer shape, and mounting holes 24 penetrating between the upper and lower surfaces 22, 23 are formed in the central portions thereof. ing. Further, the main cutting edges 26 are formed on the ridges of the side surfaces 25a, 25b located between the upper and lower surfaces 22, 23 that are parallel to the axis of the mounting hole 24.
Are formed.

Then, the rake face 27 of each main cutting edge 26 is formed at both end portions of the pair of side faces 25a, 25a which are not adjacent to each other among the side faces 25a, 25b. Then, side blades 28 are formed at the ridges where both sides of the rake face 27 and the upper and lower faces 22, 23 intersect. Further, as a result, the side faces 25b, 25b located between the side faces 25a, 25a serve as front flanks of the main cutting edges 26. And further, these pair of side surfaces 25b, 25b and the upper and lower surfaces
At the ridge line portion where 22 and 23 intersect, a channel portion 29 having an angle β of about 45 ° is formed over the entire length in the width dimension of 0.5 mm to 1.5 mm. This allows the main cutting edge 26
A chamfer blade 30 is formed between the side blade 28 and the side blade 28.

Here, the width dimension of the chamber portion is set to be in the range of 0.5 mm to 1.5 mm, because if the dimension is less than 0.5 mm, the chamber portion 29 is smaller than the lift amount L of the turning broach or the like in the normal cutting process. As a result, a part of the upper and lower surfaces 22, 23 is rubbed against the work surface of the work material W. On the other hand, when the width dimension exceeds 1.5 mm, the main cutting edge 26 and the changer blade involved in cutting are involved. This is because the total length dimension of 30 and 30 becomes large, which in turn causes an increase in cutting resistance, which is unsuitable for each.

In the chip 21 having the above configuration, the front flank 25b
Since the chamfer portion 29 is formed at the ridge line where the upper and lower surfaces 22 and 23 intersect, a front clearance angle γ is added to the workpiece W in the radial direction as shown in FIGS. 2 to 4. When cutting is performed,
An escape angle α is formed in the changeover portion 29. here,
The clearance angle α is represented by tan α = tan γ · cos β when the Changhua angle is β and the front clearance angle is γ.

By the way, when γ = 8 ° and β = 45 °, α≈5 ° 40 '.

Further, as shown in FIGS. 5 to 7, in order to avoid the interference between the upper and lower surfaces 22, 23 and the work material W in the processing of simultaneously cutting the work material W in the axial direction and the radial direction, Even when the side cutting edge angle δ ₂ and the side clearance angle δ ₁ are provided, the clearance angle α ₁ is formed in the channel portion 29.

Therefore, according to such a chip 21, the upper and lower surfaces 22 and 23 of the chip 21 are not rubbed by the side surfaces of the workpiece W to be machined and the life thereof is shortened in any cutting process. Moreover, in this chip 21, the main cutting edges 26 can be formed at all four corners.

In the above embodiment, the case where the chip 21 is attached to the turning broach has been described, but the present invention is not limited to this, and the same effect can be obtained even when the chip 21 is attached to a cutting tool such as a cutting tool and used as its cutting edge. The effect can be obtained.

[Effects of the Invention] As described above, the throw-away tip used by being attached to the turning broach according to the present invention forms the rake face of each main cutting edge on both end portions of a pair of side surfaces that are not adjacent to each other, and A chamfer with a width of 0.5 mm to 1.5 mm is formed over the entire length at the ridgeline where the pair of side faces, which are the front flanks of the main cutting edge, sandwiched between the pair of side faces and the upper and lower faces intersect. As a result, a chamfer blade is formed between the main cutting edge and the side edge, so that the main cutting edge can be formed at all four corners, and in both axial and radial cutting processing. However, the upper and lower surfaces are not abraded by the work material. Therefore, it is possible to avoid the early wear of the throw-away tip mounted on the turning broach, extend the life of the turning broach, and eventually reduce the cost.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of the chip of the present invention, and FIGS. 2 to 4 show the cutting state of a work material by the chip in the radial direction. FIG. 2 is a front view and FIG. Is a side view, 4th
The figure is a view from the IV direction in FIG. 2, and FIGS. 5 to 7 also show the cutting state of the work material in the axial direction. FIG. 5 is a plan view, FIG. 6 is a front view, and FIG. FIG. 7 is a view taken in the direction of VII in FIG. 6, FIG. 8 is a perspective view showing a conventional chip, and FIGS. 9 to 11 show the cutting state of the work material in the radial direction by the chip. The figure is a side view, FIG. 10 is a front view, FIG. 11 is an enlarged view of “A” part in FIG. 9, and FIGS. 12 and 13 show a cutting state according to a modification of the above chip. The figure is a plan view,
FIG. 13 is a front view, and FIGS. 14 to 16 show cutting states in the axial direction by the chip shown in FIG. 8. FIG. 14 is a plan view, and FIGS. 15 and 16 are front views. . 21 …… Chip (throw away chip), 22 …… Top surface,
23 …… Bottom surface, 24 …… Mounting hole, 25a, 26b …… Side surface, 26 ……
Main cutting edge, 27 ... rake face, 28 ... side edge, 29 ... Cyanhua part, 30 ... Cyanhua blade, α ... clearance angle.

Claims (1)

[Scope of utility model registration request] 1. A rectangular plate-shaped outer appearance, mounting holes penetrating between the upper and lower surfaces are formed in the central portions of the upper and lower surfaces, and an axis line of the mounting holes on the side surfaces located between the upper and lower surfaces. In a throwaway tip having parallel ridges as main cutting edges, and side blades formed on the ridges where the rake face of the main cutting edges and the upper and lower surfaces intersect, both ends of a pair of side surfaces not adjacent to each other In the portion, the rake face of the main cutting edge is formed, and the ridge line portion where the pair of side surfaces and the upper and lower surfaces which are sandwiched between the pair of side surfaces and are the front flanks of the main cutting edge intersect with each other, Width is 0 over the entire length.
A throwaway tip for use in a turning broach, characterized by forming a chainer portion having a range of 5 mm to 1.5 mm, thereby forming a chainer blade between the main cutting edge and the side blade.