RU2477674C1 - Double-sided cutting plate - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to machine building and may be used for milling. Cutting plate has two identical opposite end surface with larger and smaller angles and two opposite identical major side surfaces, four major cutting edges lagging one from another and formed at intersection of major lateral surface and end surface, and major rear surface adjoining said major cutting edge.Tangential lines to major rear surface extending from appropriate major cutting edge are inclined to plate mean plane at acute angle in every cross-section of cutting plate. Plate every end surface has four auxiliary cutting edges and six pairwise diagonally opposite angles located at vertices of irregular convex or concave hexagon, two of which are smaller and four are larger. Smaller angles are located at larger diagonal of irregular convex hexagon or at minimum inner diagonal of irregular concave hexagon. One pair of diagonally opposite angles on every end surface smaller angle and minimum diagonal is located between diagonally opposite smaller angles relative to plate mean plane between diagonally opposed larger or smaller diagonal of hexagon.

EFFECT: higher reliability and precision of cutting plate positioning.

6 cl, 18 dwg

Description

Technical field

The present invention relates to a double-sided indexable cutting insert used in a metal cutting process.

State of the art

In the patent of the Russian Federation RU 2358844 C2, a two-sided cutting insert is disclosed having two identical opposed end surfaces and two opposite identical main side surfaces, four main cutting edges lagging one from another, each of which is formed at the intersection of the main side surface and the end surface, and the main rear a surface adjacent to each major cutting edge. In each cross section, by a plane perpendicular to the main side surfaces, lines tangent to the main rear surface and extending from the corresponding main cutting edge are inclined to the middle plane of the insert at an acute angle. To increase the strength of the cutting insert due to its tangential installation, each end surface has four angles, two diagonally opposite lowered angles, and two diagonally opposite lowered angles, and the lowered corners are closer to the middle plane than the raised angles. Each end surface has two raised corner cutting edges and two lowered corner cutting edges. It should be noted that if it is necessary to reduce radial forces in the case of installing this plate in face mills with a main angle of less than 90 degrees, the roughness of the machined surface deteriorates and the strength of the tips of the cutting insert decreases. In addition, when installing this plate on end and face mills with a main angle of 90 degrees, it is not possible to process the surfaces of the parts with an inclined axial (Ramping) insert.

A double-sided cutting insert for use in milling cutters is disclosed in RU 2337795. This double-sided cutting insert at each end has two identical opposed face surfaces of a generally rectangular shape in a plan view having four angles. Moreover, each end surface has two diagonally opposed understated and two diagonally opposed elevated angles. Each auxiliary lateral surface is divided into two auxiliary subsurfaces by an edge, and each of the auxiliary subsurfaces extends from the specified rib at an angle of 1-2 degrees. It should be noted that on the auxiliary cutting edges of the specified insert there are sections with a negative rake angle, which does not allow axial oblique insertion during processing of parts and reduces the technological capabilities of this insert.

The tangential cutting insert disclosed in patent RU 2354511 includes two opposed end surfaces having a generally rectangular shape in a plan view of the cutting insert and located mirror symmetrically with respect to the middle plane of the cutting insert passing between them, a peripheral side surface located between opposing end surfaces. The peripheral side surface includes two opposite main side surfaces having a generally isosceles trapezoidal shape in the main views from the side to the cutting insert, each end surface has four angles, two of which are diagonally opposite, raised and two diagonally opposite, lower, located closer to the middle plane of the cutting plates, than elevated angles, a supporting surface is made on each end surface. This insert has a limited number of main cutting edges when used on face mills, for example, on mills with right rotation there are only two main cutting edges.

An object of the present invention is to provide an improved double-sided cutting insert.

The problem is solved by means of a set of features given in the relevant claims. In particular, a tangential double-sided cutting insert is proposed, having a top view, preferably in the form of an irregular convex or concave hexagon with a negative static rear angle, having a through hole for a mounting screw not passing through the chip surfaces, and the angle of the main rear surface is measured with respect to the middle plane plates. Its final form is preferably obtained by compression or casting.

SUMMARY OF THE INVENTION

According to the present invention, there is provided a double-sided cutting insert for a milling cutter having:

two identical opposite end surfaces and a peripheral side surface located between them, including two opposite identical main side surfaces with an opening passing between them and through them,

raised and lowered corners and corner edges, made in the form of cutting corner edges, end surfaces,

four main cutting edges lagging one from another, each of which is formed at the intersection of each main side surface with each end surface,

the main rear surface adjacent to each main cutting edge, and

in each cross section of the insert with a plane generally perpendicular to the main side surfaces, lines tangent to each main side surface and extending from their corresponding main cutting edge are inclined to the middle plane of the insert at an acute angle.

In accordance with the present invention, each end surface has six pairwise diagonally opposite angles, and

in the middle plane section, the cutting insert is preferably in the form of an irregular convex or concave hexagon,

on each end surface has two diagonally opposite ones, respectively, the largest with a convex hexagon and the smallest internal diagonal with a concave hexagon of underestimated angle,

four pairs of opposite angles from respectively the largest or smallest internal diagonal of the hexagon;

on each end surface, one pair of raised diagonally opposed angles is located with respect to the middle plane of the cutting insert between the diagonally opposed angles and the second pair of raised diagonally opposed angles on the respectively largest or smallest internal diagonal of the hexagon,

each end surface has four elevated cutting corner edges and two lowered corner edges formed at the intersection of the side surfaces of the plate with the end surface,

each major cutting edge extends between respective raised angled edges,

the peripheral side surface of the cutting insert includes four pairwise diagonally opposite identical auxiliary side surfaces with auxiliary cutting edges formed at the intersection of each auxiliary side surface with each end surface,

each end surface has four auxiliary cutting edges, each of which extends between a corresponding raised corner edge and a lowered corner edge.

In accordance with one preferred embodiment, in each longitudinal section of the insert with a plane substantially parallel to the mid-plane of the insert, the line of intersection with each major rear surface is made in a straight line.

In accordance with another preferred embodiment, in each longitudinal section of the cutting insert with a plane essentially parallel to the middle plane of the cutting insert, the intersection line with each major rear surface is made in the form of a convex curve.

In accordance with another preferred embodiment, in each longitudinal section of the cutting insert with a plane generally parallel to the middle plane of the cutting insert, the line of its intersection with each front surface is made in the form of a straight line.

In accordance with another preferred embodiment, in each longitudinal section of the cutting insert with a plane generally parallel to the middle plane of the cutting insert, the line of its intersection with each front surface is made in the form of a concave curve.

In accordance with another preferred embodiment, in each longitudinal section of the cutting insert with a plane generally parallel to the middle plane of the cutting insert, the line of its intersection with each major rear surface is made in the form of a wavy line.

Brief Description of the Drawings

For a better understanding, but only as an example, the invention will be described with reference to the attached drawings, in which:

on figa shows a perspective view of a cutting insert in accordance with the present invention, having in the middle section the shape of a convex irregular hexagon,

on figv shows a perspective view of a cutting insert in accordance with the present invention, having in the middle section the shape of a concave irregular hexagon,

on figa shows a first side view of the cutting insert in figa,

on figv shows the first side view of the cutting insert on figv,

on figa shows a top view of the cutting insert shown in figa,

on figv shows a top view of the cutting insert shown in figv,

on figa shows a second side view of the cutting insert shown in figure 1 a,

on figv presents a second side view of the cutting insert shown in figv,

on figa partially shows the cross section of the cutting insert shown in figa, along the line VA-VA on figa,

on figa partially shows the cross section of the cutting insert shown in figv, along the line VA-VA on figv,

on figa partially shows the cross section of the cutting insert shown in figa, along the line VB-VB in figa,

on figv partially shows the cross section of the insert shown in figv, along the line VB-VB on figv,

on figa partially shows the cross section of the cutting insert shown in figa, along the line VC-VC in figa,

on figv partially shows the cross section of the cutting insert shown in figv, along the line VC-VC in figv,

figure 6 partially shows a cross section of the cutting insert shown in figa and 1B, along the line VE-VE respectively figa and figv,

in Fig.7 partially shows a cross section of the cutting insert, similar to Fig.6, but with curved convex rear surfaces,

on Fig partially shows a cross section similar to Fig.6, but with concave front surfaces,

figure 9 partially shows a cross section similar to figure 6, but with curved rear surfaces.

Detailed description of the drawings.

Refer to FIGS. 1-9, showing a cutting insert 10 in accordance with the present invention. The cutting insert 10 is indexable. It is preferably made by shaped or injection molding and sintering carbide powders. The cutting insert 10 has two identical opposite end surfaces, mainly in the form of an irregular convex or concave hexagon in a plan view of the cutting insert. Each end surface 12 has a 180 degree rotational symmetry about the first axis A1 passing through two end surfaces 12.

The peripheral side surface 14 is located between two opposite end surfaces 12 and includes four identical pairwise opposing auxiliary side surfaces 16, two opposite identical main side surfaces 18 mainly in the form of a parallelogram. Each of the two opposite identical main side surfaces 18 has a 180 degree rotational symmetry about the second axis A2, perpendicular to the first axis A1 and passing through the opposing main side surfaces 18. Similarly identical pairwise opposing auxiliary side surfaces 16 have 180 degree symmetry with respect to the third axis A3 passing through the largest inner diagonal with a convex irregular hexagon or the smallest diagonal diagonal with a concave irregular hexagon perpendicularly to the first axis A1 and second axis A2. The minor plane P1 of the cutting insert 10 is defined by the first axis A1 and the second axis A2, and the middle plane M of the cutting insert is defined by the second axis A2 and the third axis A3. The cutting insert 10 is made with a through hole 22 extending between and open to the main side surfaces 18. The hole 22 has an axis B which coincides with the second axis A2. The through hole 22 is designed to accommodate a mounting screw therein to secure the cutting insert 10 to the milling cutter.

Each end surface 12 has four pairwise opposite elevated angles 28, 30 and two diagonally opposed understated angles 36. The elevated angles 30 of each end surface 12 lie in the plane P of the end surface. The middle plane M is parallel to the planes P of the end surfaces 12 and lies between them. In cross section by the middle plane M, the cutting insert 12 is in the form of a preferably irregular convex or concave hexagon. Lowered angles 36 are located on the largest diagonal of the convex irregular or smallest internal diagonal of the irregular concave hexagons of the end surfaces 12 closer to the plane M. The raised diagonally opposite corners 28 are located between the raised diagonally opposite corners 30 and the lowered angles 36.

On each end surface 12, the peripheral edge contains two main cutting edges 34 formed by the intersection of the main side surfaces 18 with the end surface 12, four auxiliary cutting edges 48, 52, of which two auxiliary edges 48 extend between the corresponding raised corner edge 58 and the lowered corner edge 54, two auxiliary edges 52, each of which extends between the raised corner edge 56 and the lowered corner edge 54.

The main dimension D1 of the cutting insert 10 is defined between the planes P of the end surfaces, and the auxiliary size D2 of the cutting insert 10 is defined between the main side surfaces 18 of the cutting insert 10 (see FIG. 3). The cutting insert 10 of the present invention is preferably a tangential cutting insert, therefore, the main dimension D1 is preferably larger than the auxiliary dimension D2.

On each end surface, front surfaces 44 are formed adjacent to the main and secondary cutting edges 34, 36 and the corner cutting edges 40, 42. The front surfaces 44 extend from the main and secondary cutting edges 34, 36 and from the corner cutting edges 40, 42 in the direction inside the cutting insert 10 to the inner end surface 46. If necessary, the inner end surface 46 of each end surface 12 is made flat, and the inner end surfaces of the end surfaces are parallel to each other.

. Продольные сечения главных задних поверхностей могут быть прямолинейными, как показано на фиг.6, или они могут быть выпуклыми или выпукло-вогнутыми, как показано на фиг.7, 9. Продольные сечения передних поверхностей 44 могут быть прямолинейными, как показано на фиг.6, или вогнутыми, как показано на фиг.8.Each main side surface 18 comprises a main rear surface 50 adjacent to the main cutting edge 34 and extending from it in the direction to the middle plane M. In each cross section, the plane of the cutting plate 10, generally perpendicular to the main side surface 18 of the cutting plate 10, line L (LA, LB, LC), located tangentially to the main rear surface 50 on the main cutting edge 34, is inclined to the middle plane M of the cutting insert 10 at an acute internal angle

. The longitudinal sections of the main rear surfaces may be rectilinear, as shown in FIG. 6, or they may be convex or convex-concave, as shown in FIGS. 7, 9. The longitudinal sections of the front surfaces 44 may be rectilinear, as shown in FIG. 6 , or concave, as shown in FIG.

The cutting insert 10 in accordance with the present invention is preferably made of carbide powders by compression or injection molding to the final shape and then sintered. The main side surfaces 18 of the cutting insert 10 can be ground to increase the accuracy of its positioning in the slot of the cutter. Also, to increase the accuracy of positioning of the insert 10 in the milling slot, auxiliary side surfaces 16 can be ground.

Although the present invention has been described with a certain degree of detail, it should be understood that various changes and modifications can be made without departing from the essence and scope of the invention set forth in the following claims.

Claims (6)

1. A double-sided cutting insert (10) for use in milling cutters, comprising two identical opposed end surfaces (12) and a peripheral side surface located between them, including two opposite identical main side surfaces (18) with a hole passing between them and through them, elevated and understated angles and angular edges, made in the form of cutting corner edges, end surfaces, four main cutting edges lagging one from another (34), each of which is formed at the intersection of each eye a distinct lateral surface (18) with each end surface (12), the main rear surface (50) adjacent to each main cutting edge (34), and in each cross section of the cutting insert (10) a plane mainly perpendicular to the main side surfaces ( 18) lines (L, LA, LB, LC) tangent to each main rear surface (50) and extending from the corresponding main cutting edge (34), are inclined to the middle plane (M) of the cutting plate (10) at an acute internal angle

and wherein each end surface (12) comprises a front surface (44) adjacent to each main cutting edge (34) and extending from the main cutting edges mainly in the direction inward of the cutting insert (10) to the inner end surface (46), characterized in that each end surface (12) has six pairwise diagonally opposite angles (28, 30, 36), and in the section with the middle plane (M), the cutting insert (10) has the shape of a preferably irregular convex or concave hexagon and on each end surface (12) and there are two diagonally opposite diagonally opposite angles (36) on the largest or smallest inner diagonal of this hexagon (36) and four diagonally opposite diagonally opposite sides on both sides, respectively, of the highest or smallest inner diagonal of this hexagon of elevated angles (28, 30), while of each end surface (12), one pair of raised diagonally opposite angles (28) is located in relation to the middle plane (M) of the cutting insert (10) between diagonally opposite with the largest or smallest internal diagonal of the hexagon with lowered angles (36) and a second pair of raised diagonally opposite angles (30), each end surface has four raised cutting corner edges (56, 58) and two lowered corner edges (54) formed at the intersection of the side surfaces inserts with an end surface, with each main cutting edge (34) passing between the corresponding raised angular edges (56) and (58), while the cutting insert (10) is made with a peripheral side surface (14), including four pairwise diagonally opposite identical auxiliary side surfaces (16) with auxiliary cutting edges (48, 52) formed at the intersection of each auxiliary side surface (16) with each end surface (12), each end surface (12) has two auxiliary cutting edges (48), each of which extends between a corresponding raised corner edge (58) and a lowered corner edge (54), and two auxiliary cutting edges (52), each of which extends between a raised lovoy edge (56) and lowered corner edge (54). 2. The cutting insert (10) according to claim 1, characterized in that in each longitudinal section of the plane, essentially parallel to the middle plane (M) of the cutting insert (10), the line of its intersection with each main rear surface (50) is made in the form straight. 3. The cutting insert (10) according to claim 1, characterized in that in each longitudinal section of the plane, essentially parallel to the middle plane (M) of the cutting insert (10), the line of its intersection with each main rear surface (50) is made in the form convex curve. 4. The cutting insert (10) according to claim 1, characterized in that in each longitudinal section of the plane, essentially parallel to the middle plane (M) of the cutting insert (10), the line of its intersection with each front surface (44) is made in the form of a straight line . 5. The cutting insert (10) according to claim 1, characterized in that in each longitudinal section, essentially parallel to the middle plane (M) of the insert (10), the line of its intersection with each front surface (44) is made in the form of a concave curve. 6. The cutting insert (10) according to claim 1, characterized in that in each longitudinal section, essentially parallel to the middle plane (M) of the cutting insert (10), the line of its intersection with each main rear surface (50) is made in the form of a wavy lines.

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