A blade portion for a grooving tool includes opposite first and second surfaces, a blade width thereof being defined as a shortest distance between the first and second surfaces, opposite third and fourth surfaces, and a fifth surface and an opposite blade portion end. The blade width is constant or substantially constant from the fifth surface up to the blade portion end. An insert seat separating the third surface and the fifth surface is arranged to receive an insert having a main cutting edge, an associated rake face, and an associated main clearance surface. The main cutting edge defines an insert width being greater than the blade width. A shortest distance from the fifth surface to the opposite blade portion end is greater than a shortest distance from the third surface to the fourth surface.

A drilling tool with: a shaft; a seat at one end of the shaft; a drill bit, which is arranged on the seat; and a clamping section, which is provided on the shaft and can interact with the drill bit. Also provided is a tensioning screw, which is screwed into the shaft and comprises an expanding section as well as a contact section. The expanding section interacts with the clamping section, and the contact section interacts with the drill bit.

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 for boring (40) that is attached to a machining apparatus and used for cutting a hole (13) on a large-diameter side of a stepped hole of a workpiece (10) is provided. The cutting tool for boring (40) is a set of two tools, and each cutting tool for boring (40a, 40b) in the set of two includes a shaft part (41), a cutting blade (42) laterally protruding from the respective shaft parts (41), and an abutment surface (43) formed at the tip of each shaft part (41) and used to cause the tips of the respective shaft parts (41) to butt against each other. Each cutting tool for boring (40a, 40b) performs cutting while the two cutting tools for boring (40a, 40b) rotate integrally around the center line of the shaft parts (41) in a coupled state in which the tips of the cutting tools for boring (40a, 40b) are butted together.

A cutting tool for boring (40) that is attached to a machining apparatus and used for cutting a hole (13) on a large-diameter side of a stepped hole of a workpiece (10) is provided. The cutting tool for boring (40) is a set of two tools, and each cutting tool for boring (40a, 40b) in the set of two includes a shaft part (41), a cutting blade (42) laterally protruding from the respective shaft parts (41), and an abutment surface (43) formed at the tip of each shaft part (41) and used to cause the tips of the respective shaft parts (41) to butt against each other. Each cutting tool for boring (40a, 40b) performs cutting while the two cutting tools for boring (40a, 40b) rotate integrally around the center line of the shaft parts (41) in a coupled state in which the tips of the cutting tools for boring (40a, 40b) are butted together.

A fixing device for fixing a boring bar on a material-removing machine includes a reducing sleeve with a hollow profile arranged on a front face which faces away from a machine chuck. The boring bar is received in the interior of the hollow profile. An end region of the boring bar projects from the hollow profile and carries a cutting tool. The hollow profile has a wall arranged between a hallow profile interior and a hollow profile outer wall. The wall has a lateral region where the cutting tool projects from the boring bar, a first thickness in the lateral region, and a second thickness outside the lateral region. The first thickness is less than the second thickness. A longitudinal axis of the hollow profile is parallel to and at a distance from the axis of the reducing sleeve which is coaxial with the interior of the boring bar.

A fixing device for fixing a boring bar on a material-removing machine includes a reducing sleeve with a hollow profile arranged on a front face which faces away from a machine chuck. The boring bar is received in the interior of the hollow profile. An end region of the boring bar projects from the hollow profile and carries a cutting tool. The hollow profile has a wall arranged between a hallow profile interior and a hollow profile outer wall. The wall has a lateral region where the cutting tool projects from the boring bar, a first thickness in the lateral region, and a second thickness outside the lateral region. The first thickness is less than the second thickness. A longitudinal axis of the hollow profile is parallel to and at a distance from the axis of the reducing sleeve which is coaxial with the interior of the boring bar.

A boring bar has a generally cylindrical elongate tool body has a proximal end for mounting to drive unit and a distal end for attachment to a tool head. A passageway extends longitudinally along the central axis of the elongate tool body. A plurality of longitudinally extending cavities are disposed annularly about the tool body. A compressive material is disposed in each of the cavities. An adjustable compression fitting is disposed in at least one end of each of the cavities, where each of the compression fitting can be adjusted to change compression of the material disposed in a respective cavity.

A machining apparatus includes: a shuttle unit (3) that holds a differential case (10) and rotates the differential case (10); a pair of opposed right and left machining units (4); and a tool support (6) that supports a tool (40) for machining the differential case (10), in which the pair of right and left machining units (4) each include a slide mechanism dedicated for uniaxial sliding in right and left directions, the shuttle unit (3) is movable in up and down directions and front and back directions, a tool attached to each of the pair of right and left machining units (4) enables machining an end portion of an inner surface of the differential case (10) and a flange hole of the differential case (10), the end portion surrounding a through hole, and a cutting edge of the tool (40) supported by the tool support (6) enables spherically cutting the inner surface of the differential case (10) held and rotated by the shuttle unit (3).

A tool body includes a damping apparatus having a damper mass body with an axial through bore and a central tube received in the through bore and surrounded by a cavity. An elastic element is arranged on each side of the damper mass body and provided with two socket-like portions extending axially through a central hole of two disc-like members clamping the elastic element therebetween. The socket-like portions project in a rest state of the elastic element extend axially beyond the respective axially directed side of the respective disc-like member and are in an assembled state of the tool body compressed for sealing the cavity with respect to the exterior.