To make it possible for bores (16) that are in line with one another to be efficiently worked by means of a boring bar (2), the boring bar has a main body (10) with an axis of rotation (R) and a number of cutting elements (12, 12A) at intervals from one another in the axial direction (4) and also guiding elements (14) for guiding the main body (10) in a guiding bore (16A). The guiding elements (14) are kept at a distance from the axis of rotation (R) equivalent to a guide radius (r1). The main body (10) is divided into a functional region (19) and an eccentric region (10), wherein the cutting elements (12, 12A) and the guiding elements (14) are arranged such that they are distributed around the main body (10) over an angular range (a) of less than 180°. Furthermore, the circumferential side (22) of the main body (10) can be passed eccentrically through a respective bore (16, 16A) of which the unworked tube radius (r2) is less than the guide radius (r1).

A holder in a non-limiting aspect of the present disclosure may include a base having a bar shape extended from a first end to a second end along a central axis, and a first weight having a column shape and a second weight having a column shape. The base may include a cavity extended along a central axis. The first weight may be located in the cavity. The second weight may be located in the cavity and located closer to the second end than the first weight.

A high-speed tool holder includes: a tool shaft for accommodating a tool at its first end, and a machine clamping part which is integrally connected to the tool shaft and forms an interface for clamping in the machine; with the tool shaft being substantially truncated circular cone-shaped, a first diameter at the first end with the tool insertion opening being smaller than a fifth diameter at the second end at the machine clamping part; and a portion of the substantially truncated circular cone-shaped tool shaft having an outwardly bulging, preferably spherical, shape between the tool insertion opening and the machine clamping part.

A tool holder is provided comprising a base body for coupling with a drive spindle that can be driven rotatingly, whereon a clamping chuck for clamping a tool is provided, further comprising a damping element arranged between the base body and the clamping chuck, wherein the damping element is made of an elastomeric material or of a shape memory alloy, and wherein the clamping chuck is solely connected to the base body by means of the damping element.

An elongated tool holder includes a tool anti-vibration component having a mass housing portion and an anti-vibration arrangement. The anti-vibration arrangement includes an enclosed interior holder cavity formed in the mass housing portion. The anti-vibration arrangement also includes a vibration absorbing mass disposed within the holder cavity and elastically suspended therein by at least three non-torus shaped, resilient suspension members contacting an inwardly facing cavity wall surface. A cutting tool is provided with the tool holder.

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 elongated tool holder includes a mass housing portion having a housing peripheral surface, an outer sleeve having a sleeve hole wall surface, and an anti-vibration arrangement. An elongated groove is formed in one of the housing peripheral surface and the sleeve hole wall surface. In an assembled state of the tool holder, the groove, which is located at a common interface of the housing peripheral surface and the sleeve hole wall surface, forms a groove coolant channel. The groove coolant channel forms part of an overall tool holder coolant channel which is spaced apart from the anti-vibration arrangement, and thus isolates the coolant from the anti-vibration arrangement. A cutting tool incorporates the tool holder.

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.