A tool insert includes first, second, and third teeth arranged on a surface of the tool insert. The first tooth is arranged at a proximal end of the tool insert surface and has an angled leading end and a first tooth height. The second tooth is spaced from the first tooth by a first distance along the surface of the tool insert and has a second tooth height greater than the first tooth height. The third tooth is spaced from the second tooth by a second distance along the surface of the tool insert and has an extending angled portion. The first tooth forms a first groove in a bore surface. The second tooth increases the depth of the first groove. The third tooth provides at least one micro-scratch to one of the first groove and the bore surface.

A tool insert includes first, second, and third teeth arranged on a surface of the tool insert. The first tooth is arranged at a proximal end of the tool insert surface and has an angled leading end and a first tooth height. The second tooth is spaced from the first tooth by a first distance along the surface of the tool insert and has a second tooth height greater than the first tooth height. The third tooth is spaced from the second tooth by a second distance along the surface of the tool insert and has an extending angled portion. The first tooth forms a first groove in a bore surface. The second tooth increases the depth of the first groove. The third tooth provides at least one micro-scratch to one of the first groove and the bore surface.

This disclosure relates to a machine tool comprising a tool holder which rotates relative to a workpiece to be machined and has a tool axis, and a plurality of cutting inserts that are removably attached to the tool holder, the active cutting edges of said cutting inserts having a common cutting circle which is coaxial to the tool axis. According to this disclosure, the tool holder has a cylinder-type insert seat shell for radially positioning the cutting inserts, which rotates about the tool axis. The cutting inserts have at least one contact surface that can be brought into contact with the insert seat shell.

The flow of heat energy from the cutting edge rim of a self-propelled round annular rotary cutting element (insert) to axial-load and radial-load bearings in a cartridge which rotatably supports the insert on a machine tool body is reduced by defining heat flow paths from the insert rim to cartridge components which engages the bearings to have low thermal conductance relative to heat flow paths from the insert rim to other parts of the cartridge. Control over heat flow path thermal conductance is obtained by selection of materials used between the insert rim and the mentioned cartridge components, by reductions in the cross-sectional areas of the critical heat flow paths, and by combinations of those two techniques. Protection of the bearings from heat enables the insert and the cartridge to be reduced in size. Improved mountings of insert-supportive cartridges to tool bodies are disclosed. The insert and the cartridge preferably are shaped to enable the insert to be positioned on a tool body so that the insert's rake face can have a positive rake orientation relative to a workpiece. Arrangements for controlling cuttings chip formation and for handling cuttings chips also are disclosed.

A boring head is provided comprising a tool body (1) having a main rotation axis (R) about which the tool body (1) rotates during boring operations. The boring head further comprises a tool carrier (6) arranged in or on the tool body (1), a first motor (9) for displacing the tool carrier (6) relative to the tool body (1) and a clamping mechanism (26) with a clamping element (27, 55, 68, 81) for effecting a clamping force on the tool carrier (6), in order to prevent a displacement of the tool carrier (6) relative to the tool body (1) during boring operations. The clamping mechanism (26) is an active clamping mechanism which effects a clamping force that can be adjusted actively.

A tool holder holds a cutting tool that cuts a workpiece while revolving about a rotational axis. The tool holder has a fixed part and a cutting part. The fixed part is held by a main shaft of a machine tool. The cutting part is provided integrally with the fixed part and has an asymmetric shape with respect to the rotational axis. The cutting tool is attached to the cutting part. The cutting part has a one-side part and an other-side part. The one-side part has a largest protruding amount from the rotational axis in the cutting part when viewed from an axial direction. The other-side part is located on a side of the rotational axis opposite to the one-side part. A bulk density of the one-side part is smaller than a bulk density of the other-side part.

A tool holder holds a cutting tool that cuts a workpiece while revolving about a rotational axis. The tool holder has a fixed part and a cutting part. The fixed part is held by a main shaft of a machine tool. The cutting part is provided integrally with the fixed part and has an asymmetric shape with respect to the rotational axis. The cutting tool is attached to the cutting part. The cutting part has a one-side part and an other-side part. The one-side part has a largest protruding amount from the rotational axis in the cutting part when viewed from an axial direction. The other-side part is located on a side of the rotational axis opposite to the one-side part. A bulk density of the one-side part is smaller than a bulk density of the other-side part.

The invention relates to a rotary tool (1; 101; 201) for cutting large inside diameters at the outer circumference (2) of which at least one cutting edge (4) is arranged, comprising a support structure (10; 110; 210) which indirectly or directly supports the at least one cutting edge (4), and comprising a chucking portion (24) for coupling to a tool holder, wherein the support structure (10; 110; 210) widens in an umbrella-type manner starting from a coupling portion (11) adjacent to the chucking portion (24) and is radially stiffened by a stiffening structure (12).

A device for mechanically removing material from a workpiece or bulk feedstock, thereby creating chips of removed material while producing a new surface on the workpiece or bulk feedstock. The device comprises a body and at least one round cutting insert that is tangentially mounted on the body. Location and orientation of the insert is characterized by a reference plane offset and an insert axis angle. The insert has an outwardly-facing rake surface on which chips are formed. A planar flank surface is oriented relative to a cutting motion so as to provide clearance between the cutting insert and the surface created by removal of a layer that is converted into chips. A circular cutting edge lies at the intersection of the flank and rake surfaces.

A device for mechanically removing material from a workpiece or bulk feedstock, thereby creating chips of removed material while producing a new surface on the workpiece or bulk feedstock. The device comprises a body and at least one round cutting insert that is tangentially mounted on the body. Location and orientation of the insert is characterized by a reference plane offset and an insert axis angle. The insert has an outwardly-facing rake surface on which chips are formed. A planar flank surface is oriented relative to a cutting motion so as to provide clearance between the cutting insert and the surface created by removal of a layer that is converted into chips. A circular cutting edge lies at the intersection of the flank and rake surfaces.