Sumitomo Electric Industries, Limited

Sumitomo Electric Hardmetal Corp.

Yoshikatsu Mori

Akio Hara

Christoph Zeiner

Makoto Abe

Mitsunori Kobayashi

Kazuo Noguchi

Masaaki Jindai

Andreas Widmann

Hiroshi Fujii

Nagatoshi Kunimori

Jun Maeda

Toshio Nomura

Kouki Matsubara

Nobuyuki Kitagawa

Kazutaka Isobe

Yoshiki Maeda

Ryusei Hamada

Naohiro Nakamura

Mitsuaki Noda

Kazuhiko Kashima

Hideo Mori

Keiji Honda

Naruhito Yauchi

Yoshio Dohi

Hideo Fukagawa

Yasuhiro Kajiwara

The holder has a first surface and a second surface. The head includes a cutting edge portion and a shank portion. The holder is provided with a first hole and a second hole communicating with the first hole, the first hole extending in a third direction inclined by a second angle relative to a second direction extending from the second surface toward the first surface when viewed in a direction parallel to the axis line. The shank portion has a flat surface portion, and is provided inside the second hole. The fastening portion is provided inside the first hole, and is in contact with the flat surface portion. In a plane perpendicular to the axis line, a third angle between the second direction and a fourth direction perpendicular to the flat surface portion is larger than the second angle. The third angle is less than 90&#xb0;.

Cutting tool

An indexable cutting insert comprises a flank face having a generally parallelogram shape and a plurality of side faces. The flank face is bounded by a plurality of edges. Each edge joins the flank face with one of the side faces. The plurality of edges comprises a first cutting edge and a second cutting edge. The first cutting edge has a shape corresponding to a portion of a first bent curve and the second cutting edge has a shape corresponding to a portion of a second bent curve. The second bent curve is obtainable by a translation of the first bent curve along a width direction of the cutting insert. The cutting insert has a two-fold rotational symmetry with respect to an axis of symmetry that is perpendicular to the width direction, a longitudinal direction of the cutting insert being perpendicular to the width direction and the axis of symmetry.

Indexable cutting insert, cutting insert holder, cutting tool, turning device and turning method

Cutting insert

A throw-away insert has four sets of cutting edges with high edge strength and which does not limit the amount which can be cut. An upper half portion of the insert has a set of cutting edges provided at each of two acute-angled corners of a parallelogram. The set of cutting edges includes a major cutting edge defined on one side of the parallelogram and a minor cutting edge defined on the other side and forming an angle of about 90.degree. with the major cutting edge. The lower half portion of the insert has the same structure and dimensions as the upper half portion but is configured as if the upper portion were turned over and further rotated 3.degree.-7.degree. clockwise with respect to the upper half portion. The two sets of cutting edges on the upper half portion and the two on the lower half portion constitute four sets of cutting edges in all.

Throw-away insert and face milling cutter

A drill has a pair of cutting edges (4) which are arranged at positions that are substantially uniformly circumferentially spaced about its rotation axis. Each of the cutting edges (4) has a first linear cutting region (4a) and a second linear cutting region (4b) which are aligned with each other on the same straight line, and a curved cutting region (4c) which is located between the first and second linear cutting regions (4a, 4b). The curved cutting region (4c) has a third linear cutting region (4e, 4f) which extends in a direction intersecting with the second linear cutting region (4b) at a prescribed angle. With this structure, it is possible to prevent chip loading etc. which may be caused during perforation drilling operations. In a throw-away tipped drill, a notch (118a) is formed in a received portion of an insert (110) which is mounted on a shank (130). A holding portion (131a, 131b, 133a, 133b) of the shank (130) corresponding to the notch (118a) is provided with a through screw hole (138). A male screw (139) is inserted in the through screw hole (138), and a spherical pressing member (140) is interposed between the forward end of the male screw (139) and the surface of the notch (118a) of the insert (110). With this structure, it is possible to prevent separation of the insert (110) from the shank (130).

Drill and lock screw employed for fastening the same

Throw-away tipped drill

A ball end mill having a plurality of throw away inserts. Its body is formed in its hemispherical portion at diametrically opposite positions with insert mounting pockets each having a plurality of insert mounting seats. In each set, an insert having an acruate cutting edge is mounted so that the cutting edges will generate a hemispherical locus with laps of more than a quarter of the length of each cutting edge. The inserts closer to the front end of the body has an axial rake of 0 to 5 degrees, whereas those at the rear have an axial rake of 4 to 8 degrees, the latter having a larger axial rake than that of the former. Further, the insert in each pocket are arranged so that the one at the rear will have the leading end of its cutting edge located on the extension line of the cutting edge of the one in front. Thus, the inserts as a whole form a substantially S-shaped line as viewed form the front of the body.

Ball end mill with throw away insert

A process for producing a cutting tool having a rake face and flank face which intersect to form a cutting edge, which cutting tool comprises a substrate consisting of a sintered hard metal and a coating film provided thereon consisting of a material with a higher hardness than the substrate, which method involves subjecting the substrate to a coating treatment and honing treatment in such a manner that the coating film near the cutting edge has such a thickness that the thickness continuously increases in directions away from the cutting edge along both the rake face and the flank face from a minimum value, including zero, at the cutting edge, such that the thickness of the coating at the rake face reaches a maximum thickness at a first distance from the cutting edge and the thickness at the flank face reaches a maximum thickness at a second distance from the cutting edge, wherein the first distance is greater than the second distance.

Process for the production of a cutting tool

A throwaway cutting tip (31) has two substantially polygonal main surfaces (32, 33) and cutting edges (42, 43, 44, 45, 49, 50) in the form of a curved line projecting inwardly in the direction of the thickness of the tip. The cutting edges extend between nose portions (38, 39, 40, 41) positioned at apexes of the polygon. The main surface has a flat central portion (47) in the middle. A rake surface having two portions extends between the flat central portion and the cutting edge. The rake surface (51) has a flat portion (56) and a curved, concave portion (53). The curved concave surface portion (53) connecting the lowermost edge (52) of the flat rake surface portion to the flat central portion functions as a chip breaking surface. The chip breaking is enhanced by a plurality of projections (55) arranged along the curved concave surface portion. Each nose portion has a nose protecting surface (38a, 39a, 40a, 41a) extending parallel to the flat central portion inwardly from an end edge defined between lateral surfaces (34, 35, 36, 37) and the main surface.

Throwaway tip

A drill bit structure has a drill bit body 4 and a plate-like hard tip member 9. The cutting end of the drill bit body 4 has a groove 7 extending substantially at right angles to the central drill bit axis, and the hard tip 9 is fitted and fixed in the groove 7. The web thickness is 25-35% of the drill bit diameter and the flute width ratio is 0.4:1 to 0.8:1. The rake angle of each cutting lip 10 measured at positions spaced at least 2/3 of the drill bit diameter radially outward from the drill bit center is in the range of -5.degree. to positive values.

Drill bit structure

A cutting insert having excellent toughness as well as wear resistance is provided comprising a substrate consisting of a sintered hard metal or alloy such as cemented carbides and a coating film provided thereon consisting of a material having a higher hardness than the substrate, characterized in that the coating film near the cutting edge is continuously made thinner or removed toward both the rake face and flank face.

Coated hard metal tool

A throw-away insert has a cutting edge (12) along its outer periphery and between adjacent noses (11). A concave rake surface (8) is formed which extends directly form the cutting edges (12) toward the center of the insert. A plurality of bosses (10) and a plurality of projections (9) are spaced a predetermined distance from the cutting edges (12) and extend above the rake surface (8). A plurality of lands (5) which are spaced at predetermined intervals (16) from each other are located along the cutting edge (12) and on the rake surface (8).

Throw-away insert

An improved throwaway insert is proposed which has a cutting edge, a land extending along and inside of the cutting edge, a breaker groove extending along and inside of the land, a flat central area enclosed by the breaker groove, and a plurality of semicircular projections arranged in a chip breaker groove at its corners and its straight portions to enable chip to be satisfactorily broken over wide ranges of the depth of cut and the feed. These projections rise from midway of the breaker groove until they become even with the central area enclosed by the breaker groove.

Throwaway insert

A drill made of cemented carbide, is constructed for compensating for the brittleness of cemented carbide to increase its cross-break strength. For this purpose, the ratio of the diameter c of the web portion (1) to the drill diameter d is set in the range of 25% to 35%, and the flute width ratio (b:a) is set in the range of 0.4:1 to 0.8:1. Further, to decrease the cutting resistance on the drill, the radial rake .theta..sub.r angle of the cutting lip 4 measured at positions spaced at least 2/3 of the drill diameter toward the outer peripheral side is set in the range of -5.degree. to positive valves. Furthermore, to promote the chip ejecting function, the relative distance L between the cutting lip 4 and the flute wall 5 opposed thereto, is decreased.

Cemented carbide drill bit

An improved throw away insert for a boring tool has a recess at each corner, a small chip breaking projection formed in said recess and a large chip breaking projection formed in the center of the top surface of the insert to control the chip during cutting for large depths of cut.

Growing community of inventors

Itami, Japan

Yoshikatsu Mori