A method and apparatus for machining an internal surface of a differential case. A lathe having a turret and a pair of spindles are in electrical communication with a programmable computer. Integrally connected to the turret is a cutter gripper assembly that is selectively grippingly engageable with a cutter. A differential case is mounted horizontally within a mount assembly on a tabletop of the lathe. Once the cutter gripping assembly engages the cutter, the turret moves toward the differential case until the cutter is in a start position within the hollow portion of the case aligned with openings in a first and second tubular portion of the case and the pair of spindles. The pair of spindles then drivingly engage the cutter and the cutter machines a first and second internal machining surface as the cutter moves from a first cutting position to a second cutting position.

A cutting tool including an insert and a holder to which the insert is secured. The insert has a rod with a substantially circular transverse cross-section. The insert includes a shank portion and a cutting edge portion. The cutting edge portion is located at an end portion continuous with the shank portion. In the cutting edge portion, one end of a cutting edge ridge protrudes toward the periphery of the rod. When the insert is secured to the holder, the cutting edge ridge has a negative radial rake angle.

A cutting part (1) for a tool head (2) for a lathe (3) for machining a workpiece (4), having a cutting edge (5) for removing material from the workpiece (4) and having a rake face (6) for guiding away the removed material or cuttings. The problem of providing a cutting part (1) which can be realized in a simple manner and with which lead-free materials can also be machined is solved in that a flat structure (7) is formed in the rake face (6) of the cutting part (1) adjoining the cutting edge (5) for breaking the cuttings. A lathe (3) for machining a workpiece (4), having a tool head (2) is provided with at least one such cutting part (1).

A tool holder for a machine tool, in particular for a core drilling machine, having a hollow shaft which has, at one end for coupling to the drive of the machine tool, a connector and, at the other end, a receiving opening with a plurality of openings in which locking elements are accommodated which are radially adjustable between a clamping position and an release position for securing a tool accommodated in the receiving opening. A switching sleeve is provided, which is adjustably mounted on the hollow shaft between a first switching position and a second switching position, a first subset of the locking elements being provided in the first switching position for locking the tool in the receiving opening, and a second subset of the locking elements being provided in the second switching position for locking the tool in the receiving opening, while the adjustment of the respective remaining locking elements is deactivated.

An indexable cutting insert has a central mounting portion and two cutting portions. The central mounting portion has opposing upper and lower surfaces. The lower surface has two abutment elements associated therewith, each abutment element having two diverging abutment surfaces forming two abutment angles. The two cutting portions extend away from the central mounting portion, have distal cutting edges, and are entirely located in diagonally opposite imaginary quadrants of four quadrants defined by two mutually perpendicular quadrant planes. Two abutment bisector planes bisecting the two abutment angles and one of the quadrant planes are parallel or coincident. In a top view, the two cutting portions extend away from the central mounting portion in opposite directions. Two cutting bisector lines parallel to the two directions and bisecting the two cutting edges are mutually offset. A cutting tool has an insert holder and the cutting insert removably retained therein.

The present invention provides a cutting tool that can firmly hold four types of cutting inserts by one tool main unit. A cutting insert of a cutting tool 1 has an approximately triangular stereoscopic shape including three corner portions. A tool main unit has a fixing portion that can selectively fix a plurality of types of cutting inserts, including: a negative type cutting insert of which angle of the corner portion exceeds 60°, a positive type cutting insert of which angle of the corner portion exceeds 60°; a negative type cutting insert of which angle of the corner portion is less than 60°; and a positive type cutting insert of which angle of the corner portion is less than 60°. The fixing portion has a bottom face that contacts with a bottom face of the cutting insert, and a side wall face that contacts with a side face of the cutting insert. A portion, which contacts with the cutting insert, of the side wall face of the fixing portion differs depending on the type of the cutting insert.

A damper system for a cutting tool is provided having at least one damper body that is added to a cutter body of the cutting tool to help dampen a vibration when the cutting tool is placed in use. The damper body is supported by a damper ring. The damper ring is held in place between a central support boss or hub and an adjustable top cap. The adjustable top cap can be tightened or loosened by use of a fastener element to change the amount of pressure on the damper ring. By adjusting the tension placed on the damper ring, the damper system can be tuned to better suppress vibrations when the cutting tool is placed in use.

Cutting tool holders are disclosed that include vibration dampening elements. The vibration dampening elements may extend parallel to a longitudinal plane of the cutting tool holder. The vibration dampening elements allow the cutting tool holders to have a smaller width while still providing higher grooving depth.

Rotatable assembly (10) having one end (12) adapted to be secured to a rotatable support for rotating the rotatable assembly (10) about a rotational axis (28), the rotatable assembly (10) comprising: a main body (18) having a cavity (56); a damping mass (38) arranged within the cavity (56) and movable in radial directions (30), substantially perpendicular to the rotational axis (28), relative to the main body (18); a damping structure (36) arranged to support the damping mass (38) relative to the main body (18) and arranged to damp vibrational movements of the damping mass (38) relative to the main body (18) in the radial directions (30); wherein the damping structure (36) comprises a plurality of spring elements (40); and wherein each spring element (40) has a flat appearance.

A cutting tool for metal cutting includes a tool body having an insert seat and a recess formed therein. The tool body further includes vibration damping means. The vibration damping means have a cantilever member, the cantilever member being adjacent to the recess of the tool body. The cantilever member has a cantilever beam and an end mass, wherein the cantilever member extends between a fixed end and a free end. The fixed end is permanently connected to the tool body. The cantilever beam extends from the fixed end and the end mass extends from the free end.