It is possible to reduce shoulder parts from being damaged while suppressing an increase in cutting resistance or abrasion of edges at a time of machining.

A drilling tool for drilling machining includes: at least one major cutting edge; second cutting edges that are provided on an outer side of a tool radial direction of the major cutting edge; third cutting edges that are provided on the outer side of the tool radial direction of the second cutting edges; a first honing portion that is formed at the major cutting edge; second honing portions that are formed at the second cutting edges; and third honing portions that are formed at the third cutting edges. Honing sizes of the third honing portions are larger than a honing size of the first honing portion.

Rotary cutting tools are disclosed comprising shanks and replaceable cutting inserts are provided. The shank comprises a pocket which receives an interchangeable cutting insert. The pocket includes a floor with a central pin-receiving hole, opposing pocket centering walls, and torque transmitting pocket drive walls. The cutting insert has a relatively long rear pin receivable in the central hole of the shank. A head of the cutting insert includes insert centering surfaces that contact the pocket centering walls of the shank, and insert drive surfaces that contact the torque transmitting pocket drive walls of the shank. The configurations and sizes of the shank and cutting insert features are controlled to provide improved torque transmission, rigidity and stability during operation of the rotary cutting tools.

A cutting head rotatable about a central axis, includes a tip portion and an intermediate portion. The tip portion has an axially forwardmost tip point contained in the central axis and at least two axially forward-facing front surfaces, each front surface having a radially extending cutting edge. The intermediate portion has at least two head lands circumferentially alternating with at least two chip evacuation passages, each head land having a leading edge extending axially rearwardly from the tip portion. The cutting edges are contained in an imaginary annular ring surface, and a first imaginary radial plane containing the central axis intersects the imaginary annular ring surface to form two imaginary radial cutting profiles. Each imaginary radial cutting profile has consecutively radially outward extending first, second, and third cutting profile portions, and the second cutting profile portion includes first and second concave sub-portions spaced apart by a first convex sub-portion.

A vibration damping toolholder for a metal cutting tool, the toolholder including a holder body provided with an internal cavity, which extends inside the holder body along the longitudinal axis, and which has a first cavity end at a first holder body end. The damping toolholder further includes a tuning mass, which is movably arranged inside the cavity and extends along the longitudinal axis, and which has a first tuning mass end at the first holder body end. The damping toolholder also includes a damping medium, which surrounds the tuning mass inside the cavity, and a single primary spring element, which is positioned inside the cavity. An outer spring element end is immovably fixed to a first cavity end at the longitudinal axis, and an inner spring element end is immovably fixed to the first tuning mass end at the longitudinal axis.

The combination tool (2), in particular a drilling/chamfering tool, comprises a drill (6) extending in the longitudinal direction (4) with a clamping sleeve (8), which is designed to receive the drill (6) and fasten the drill (6) at a variable length and which has a holding seat (38) for a cutting insert (12). The drill (6) comprises a cutting region (22) provided with grooves (14), wherein the grooves (14) extend helically and are formed between two grooves (14) drill backs (18). At least one of the drill backs (18) is partially flattened to form an adjustment surface (16) for the cutting insert (12), wherein the adjustment surface (16) extends helically. As a result, a length adjustment over a large length range is made possible independently of the twist angle ().

A cutting head has two radially extending cutting arms and at least one fastening recess having an opening located at least partially on one of cutting arms. Each cutting arm has a dovetail arm rear abutment surface. A tool holder has a two circumferentially spaced apart driving members. The tool holder has a pocket with two radially extending arm receiving receptacle. Each receptacle has a dovetail receptacle rear abutment surface. The tool holder has at least one through hole located in one of the driving members. When assembled, a fastening member is disposed in the through bore and engages with the fastening recess to urge each cutting arms towards a respective driving member.

A cutting head has driven surfaces and includes a head coupling pin that protrudes rearwardly from a head rear surface. The head coupling pin includes a pin recess recessed in the pin peripheral surface. A tool holder, elongated along a holder longitudinal axis, has driving members and a holder coupling hole recessed in a holder base surface. A fastening member is disposed in a holder through bore that extends from the holder base surface to a holder peripheral surface. The holder through bore is located entirely on one side of a longitudinal plane containing the holder longitudinal axis. When a cutting tool which includes the cutting head and tool holder is in a fastened position, the head coupling pin is removably retained within the holder coupling hole upon engagement with the fastening member.

A drill body of an indexable insert drill includes at least two chip flutes separated from each other in the circumferential direction of the drill body by intermediate ribs, each chip flute and each rib extending in a helically curved path. An insert seat is located at a transition between each chip flute and a front face of the drill body. Coolant ducts are arranged in and extending along a respective one of the ribs. Each coolant duct extends in a helically curved path and has an upstream end with an inlet opening and a downstream end with an outlet opening. Each coolant duct has a cross-sectional area that varies in the axial direction of the coolant duct, such that it has a smaller cross-sectional area at its outlet opening than at its inlet opening.

A rotary cutting tool includes a tool body including a chip flute portion having a plurality of helical chip flutes separated by lobes. In one aspect, a tunable vibration absorber assembly is disposed within a cavity formed in the chip flute portion. In another aspect, the tunable vibration absorber assembly is disposed within a cavity of a replaceable cutting head. In each aspect, the tunable vibration absorber assembly includes at least two tunable absorber masses, a resilient material between the one or more absorber masses and the cavity, and one or more connecting members for preventing relative angular displacement of the one or more tunable absorber masses. The at least two tunable absorber masses are suspended only by the resilient material, thereby enabling the tunable vibration absorber assembly to be tuned to a desired frequency for suppressing torsional vibration of the rotary cutting tool during a cutting operation.

A drill-bit tip plate with a first and a second apex distanced from an axis of rotation and having inner and outer cutting edges. The first-and second apex are distanced from the broad sides of the plate. A sintering mold is provided with a first punch, second punch and a sintering die having a channel with a cross-sectional shape that corresponds to the cross sectional shape of the first and second punch. A distal end of the second punch corresponds to a negative shape of the tip front end The first punch has a distal end corresponding to the negative shape of the tip rear end. Sintering powder is compacted in the channel and a force applied to the first and second punch to sinter the sintering powder into the tip. The tip is ejected by pushing the second punch into the channel until the tip is ejected.