Abstract: A boring bar tool for use with a tip is disclosed which has a tool body. The tip is mounted to one side of a forward end of the nose of the tool body. A neck is formed at a proximal end of the nose, and a shank in the form of a shaft is formed at a proximal end of the neck. The neck has a cross-sectional area in a plane perpendicular to an axis of the shank which is larger than the cross-sectional area of the shank in the plane.

Abstract: A boring bar tool for use with a tip is disclosed which has a tool body. The tip is mounted to one side of a forward end of the nose of the tool body. A neck is formed at a proximal end of the nose, and a shank in the form of a shaft is formed at a proximnal end of the neck. The neck has a cross-sectional area in a plane perpendicular to an axis of the shank which is larger than the cross-sectional area of the shank in the plane.

Abstract: An indexable cutter insert for a rotary cutter includes a plate having front and rear faces. The front face has at least one pair of first and second marginal ridges intersecting each other. The first marginal ridge is generally arcuately shaped when viewed in a direction perpendicular to the front face and serves as a main cutting edge. The second marginal ridge is short and straight and serves as a second cutting edge. The main cutting edge has a leading end portion intersecting the second cutting edge so as to define an obtuse angle therebetween. The front face serves as a rake surface for the main and second cutting edges and has a marginal surface portion disposed adjacent to the second cutting edge and the leading end portion of the main cutting edge. The marginal surface portion is convexly curved so as to slope toward the rear face toward the second cutting edge.

Abstract: In a face milling cutter, a plurality of cutter inserts are detachably mounted to an outer periphery of a forward end portion of a cutter body. The cutter inserts are arranged in peripherally spaced relation to each other about a rotary axis of the cutter body. Each of the cutter inserts has opposite faces one of which, first face being generally in the form of an octagon having eight ridgelines or a hexagon having six ridgelines, which are formed respectively into cutting edges. Each pair of adjacent cutting edges as a major edge are intersected with each other at an obtuse angle.

Abstract: An inserted rotary cutter has a tool body, at least one first insert and at least one wiper insert. The body has a plurality of insert mounting seats formed on a forward end portion thereof. Each insert is releasably mounted to a respective insert mounting seat and has had at least one end cutting edge. The inserts are arranged so that the end cutting edge of the wiper insert projects from the end cutting edge of the first insert forwardly from the body. At least one indicating mark is provided on the body for specifying the insert mounting seat, on which the wiper insert is mounted. The insert mounting seat specified by the mark has a dimensional precision within 0.01 mm in a direction along the axis of rotation.

Abstract: A ball end mill including an elongated body, a center insert, and a plurality of cutting inserts. The center insert and the cutting inserts are mounted on the forward end of the body. The center insert and each of the cutting inserts are adjacent to each other in such a manner that the center insert is located with a part thereof at the center. The center insert which is made of cemented carbide has cutting edges passing through the center axis. The cutting inserts are made of a super hard sintered compact. Each of the cutting inserts has a cutting edge aligned to the cutting edge of the center insert. The cutting edges of the cutting inserts and the center insert cooperate to draw a hemispherical path on rotation.

Abstract: An insert rotary cutter includes a cutter body having a forward end face and at least one first cutter insert releasably attached to the cutter body. The first cutter insert is of a generally triangular shape including a front face having three marginal ridges and three corner ridges. Each marginal ridge is comprised of first, second and third ridge portions. The insert has three main cutting edges each defined by a respective first ridge portion, three auxiliary cutting edges each defined by a respective third ridge portion, three corner cutting edges each defined by a respective corner ridge, and three relief cutting edges each defined by a respective second ridge portion. One of the corner cutting edges and the main and auxiliary cutting edges which intersect the corner cutting edge are indexed in active cutting position. The indexed main cutting edge extends generally axially from the body while the indexed auxiliary cutting edge extends slightly beyond the forward end face.

Abstract: In a ball end mill, a rotational locus is described by cutting edges of respective throw-away tips mounted to a tool body. The cutting edge of one of the tips and the cutting edge of the adjacent tip overlap with each other, and the center of the overlapping portion is located at a position that is substantially 45.degree. from a forward end of the cutting edge along a 1/4 arc of the rotational locus therefrom. The overlapping length is 1/4 to 1/3 of a diameter of the rotational locus in an arcuate length thereof. A planar section is formed at a side surface of at least one of the tips, which is located at a forward end of the tool body. The side surface is located adjacent a forward end of the cutting edge. A planar surface is formed at at least one of the tip pockets formed in the tool body, at a position facing toward the planar section. The planar surface is subject to a radial cutting force acting from the throw-away tip having the planar section. The planar section is abutted against the planar surface.

Abstract: A ball end mill includes an end mill body, an indexable cutter insert, a clamp screw and shift preventing mechanism. The body has an insert receiving recess formed in a forward end portion thereof. The insert has a front face, a rear face and at least two convexly curved side faces, and has at least two convexly curved main cutting edges each defined by the intersection of a respective one of the convexly curved side faces with the front face. The insert is received in the insert receiving recess with the rear face mated with the bottom face of the recess in such a manner that one of the main cutting edges is indexed in a cutting position.

Abstract: A ball end mill includes an end mill body having an axis of rotation therethrough and an indexable cutter insert releasably attached to a forward end portion of the body. The insert includes a plate having front and rear faces. The front face has at least one generally arcuate first marginal ridge with the first marginal ridge serving as a respective generally arcuate main cutting edge. The front face has at least one short second marginal ridge with the second marginal ridge serving as a respective short cutting edge. The main cutting edge has a leading end portion disposed at one end thereof and intersecting the short cutting edge in such a manner that an angle defined by the leading end portion and the short cutting edge is obtuse. The front face serves as a rake surface for the cutting edges and has a marginal surface portion disposed adjacent to the short cutting edge and the leading end portion.

Abstract: A ball end mill includes a body, an indexable cutter insert and a clamp screw. The body has a recess formed in a forward end portion thereof and a bore formed therein and opening to a bottom face of the recess. The bore includes a cylindrical portion disposed adjacent the bottom face and an internally threaded portion greater in diameter than the internally threaded portion. The insert includes a front face, a rear face and at least two convexly curved side faces. The front face has at least two convexly curved main cutting edges each defined by the intersection of a respective one of the curved side faces with the front face. The insert has an aperture formed therethrough and extending generally perpendicular to the rear face. The insert is releasably mounted in the recess with the rear face held in contact with the bottom face in such a manner that one of the main cutting edges is indexed in a cutting position.

Abstract: An insert rotary cutting tool includes a tool body of a generally circular cross-section having an axis of rotation therethrough and having an outer periphery. The cutting tool has plural groups of cutting inserts releasably mounted on the outer periphery of the body with the groups being spaced circumferentially of the body from each other. The inserts of each group are displaced circumferentially of the body and spaced axially of the body. Each of the inserts has a plurality of main cutting edges and is disposed in such a manner that one of the main cutting edges is indexed in a peripheral cutting position to serve as a peripheral cutting edge. The indexed peripheral cutting edges of the inserts are in series axially of the body as viewed circumferentially of the body. The indexed peripheral cutting edges of the inserts of each group have foremost ends disposed on a common helical line extending helically axially of the body.

Abstract: An insert boring tool includes a tool body and a cutting insert releasably mounted thereon. The insert includes a plate defined by front and rear surfaces and a plurality of side faces and having a plurality of corners where adjacent side faces intersect one another. At least one of the corners is removed to provide a corner face. A first cutting edge is defined by the front surface and one of the side faces adjacent to the corner face, and a straight second cutting edge is defined by the front surface and the corner side face. The first and second cutting edges intersect each other at an obtuse angle, and are indexed in an end cutting position. The front surface has a marginal portion extending along the second cutting edge and inclined in such a manner that a thickness of the plate between the marginal portion and the rear surface is progressively reduced toward the second cutting edge.

Abstract: An indexable cutter insert for a rotary cutter includes a plate defined by a front face, a rear face generally parallel to said front face and plural pairs of first and second side faces disposed alternately and lying between the front and rear faces. Each side face extends generally perpendicular to the front and rear faces. Each first side face is longer than each second side face and is generally arcuately convex as viewed in a direction perpendicular to the front face while each second side face is generally planar. The plate has a plurality of generally arcuate convex front cutting edges each defined by the intersection of a respective one of the first side faces with the front face and a plurality of generally arcuate convex rear cutting edges each defined by the intersection of a respective one of the first side faces with the rear face.

Abstract: An end mill includes a body having a core receiving recess and a cutting insert releasably mounted thereon. An upper surface of the insert has a first cutting edge ridge serving as an outer peripheral cutting edge, a second cutting edge ridge providing an end cutting edge and a third cutting edge ridge providing an inner peripheral cutting edge. The upper surface has a corner where the second and third cutting edge ridge intersecting each other. The upper surface is composed of a central portion and a corner portion including the corner, whereby the third cutting edge ridge comprising a first edge portion defined by a ridge of the corner portion and a second edge portion defined by a ridge of the central portion. At least that portion of the corner portion disposed adjacent the central portion is inclined providing a thickness of the insert is progressively reduced toward the corner. The insert has a negative radial rake at the outer peripheral cutting edge and a positive axial rake.

Abstract: An insert cutter includes a cutter body of a generally circular cross-section having an axis of rotation therethrough. The cutter also includes a plurality of cutter inserts releasably mounted on a periphery of the cutter body in circumferentially spaced relation to one another. Each of the cutter inserts has a main cutting edge indexed in its peripheral cutting position. The cutter inserts are disposed so that the indexed main cutting edge of at least one of the cutter inserts is provided with an axial rake angle different from axial rake angles of the indexed main cutting edges of the other cutter inserts.

Abstract: An end mill comprises an end mill body and a throw-away tip mounted on a forward end of the end mill body so as to be spaced from an axis thereof. A core receiving recess is formed at a center of a forward end face of the end mill body and has a size equal to or greater than a distance between the throw-away tip and the axis of the end mill body. The throw-away tip has an end cutting edge formed by a cutting edge ridge located adjacent the forward end of the end mill body and extending from an outer peripheral side of the end mill body toward an inner peripheral side thereof, and outer and inner peripheral cutting edges respectively formed by cutting edge ridges respectively extending from outer and inner peripheral ends of the end cutting edge toward a rearward end of the end mill body. The end mill body may mount at least two throw-away tips disposed symmetrically with respect to the axis thereof.

Abstract: A cutter insert of the indexable type for a rotary cutter includes a body of a plate of a generally circular shape and having three notches of a V-shape formed in a circumferential face of the body in equally circumferentially spaced relation, each V-shaped notch being defined by a pair of first and second opposed walls. A front face of the body cooperates with the circumferential face, interrupted by the three V-shaped notches, to define three arcuate convex cutting edges each having a leading and a trialing end. A marginal portion of the front face disposed adjacent to and extending along each cutting edge serves as a rake surface for the cutting edge, the rake surface being recessed adjacent to the first wall of the V-shaped notch so as to slope toward a rear face of the body toward the first wall to provide a convex portion extending between the front face and the first wall.