An anti-vibration damper for tools for machining of metallic work pieces is provided. For improving the damping in order to be more effective under rough includes a vibration damping device received in a hollow cylindrical space of a tool member. The vibration damping device includes a plurality of rotationally symmetrical stacked on top of each other to form a stack. A part of mutually facing upper and lower surfaces of adjacent members is spaced at a distance from each other by elastically deformable elements. The outer diameter of the stack is smaller than the inner diameter of the hollow cylindrical space of the tool member, thereby providing a cylindrical gap, which is substantially filled with spherical balls, wherein clear gap width between the inner diameter of the hollow cylindrical space and the common outer diameter of the stack deviates from any integer sum of the ball diameters.

A toolholder includes a cutting tool mounted to a head attached to a collar at a first end of the toolholder. A shank is located at a second, opposite end of the toolholder. A central cavity extends inwardly from the first end toward the shank. A passive vibration absorber assembly is disposed within the central cavity. The passive vibration absorber assembly includes an absorber body and an absorber cap attached to the absorber body. The absorber body has a first end, a second end opposite the first end, and one or more cavities formed in the second end. The one or more cavities of the absorber body are partially of wholly filled with metal or ceramic particles or powders to provide particle damping for suppressing vibration of the toolholder.

A toolholder includes a cutting tool mounted to a head attached to a collar at a first end of the toolholder. A shank is located at a second, opposite end of the toolholder. A central cavity extends inwardly from the first end toward the shank. A viscous fluid inertia mass damper is disposed within the central cavity. The viscous fluid inertia mass damper includes an absorber body having a first end, a second end opposite the first end, a fluid reservoir formed in the damper body for containing a viscous fluid, and a plurality of apertures formed in the damper body for allowing the viscous fluid to flow from the fluid reservoir and through the apertures to suppress vibration of the toolholder. A method for suppressing vibrations in a toolholder is also disclosed.

A tunable or tuned boring tool having a dynamic vibration absorber is provided herein. The boring tool includes a boring bar having a distal portion configured to support a tool, a proximal portion configured for attachment to a support structure of a metalworking machine, and a cylindrical body extending between the proximal portion and the distal portion, having an elongated cavity therein. The boring tool further includes a tuned or tunable absorber inserted in the cavity of the boring bar. The absorber includes an absorber mass, an annular or partially annular support circumscribing each end of the absorber mass for holding the absorber mass within the cavity, and a layer of fluid restricting material surrounding at least a central portion of the absorber mass for dampening vibration of the absorber mass. A method of forming a boring tool with a dynamic vibration absorber is also provided herein.

An anti-vibration device for the machining of a shaft includes a first fixed ring intended to be kept inside a shaft by a shoulder, the anti-vibration device including: at least one first external groove and at least one first external seal for forming at least one contact with the internal surface of the shaft; at least one first internal circumferential groove and at least one first internal seal for forming at least one contact with the external surface of the bar; an internal circumferential cavity that is able to cause the circulation of a fluid arriving through a first duct and leaving through a second duct, the first duct and second duct passing through the radial thickness of the anti-vibration device, the internal circumferential cavity making it possible to realize a vibration-damping function when a fluid passes through it.

A tuned or tunable boring tool includes a boring bar defining an elongated cavity therein. A distal end of the boring bar is configured to support a tool or cutting insert. The boring tool further includes a dynamic vibration absorber inserted within the elongated cavity of the boring bar. The dynamic vibration absorber includes a mass that vibrates in conjunction with vibration of the boring bar. The mass has a proximal end and a distal end. The dynamic vibration absorber further includes at least one resilient proximal support positioned adjacent to and supporting the proximal end of the mass and at least one distal resilient support positioned adjacent to and supporting the distal end of the mass. The at least one proximal support and at least one distal support have a different stiffness.

A cutting tool has a tool body with a proximal end for mounting to drive unit and a distal end for engaging a workpiece for cutting. The tool body extends longitudinally along a central axis of the tool body. The tool body defines an interior space therein. One or more additively manufactured passive dampers are disposed in the interior space of the tool body.

A lightweight vibration damping cutting tool bar includes a tool body, on which a plurality of cavities are opened along the length direction, and the cutting tool body between adjacent cavities have a BCC lattice structure, the closed magnetic pole device includes a plurality of magnetic pole pieces located at the bottom and side walls of the cavity respectively; the pendulum damper is placed inside the closed magnetic pole device composed of a plurality of magnetic pole pieces, the outer surface of the pendulum damper is provided with a magnetic pole patch corresponding to each magnetic pole piece one by one, the magnetic pole patch is set relative to the side with the same polarity of each magnetic pole piece, so that the magnetic force of each magnetic pole piece and the magnetic force of the corresponding magnetic pole patch are repelled.

A non-rotating boring tool for internal turning includes a boring bar having an elongated body, a cutting element with a rake side, a relief surface and a cutting edge, and an electrically controlled vibration actuator for active vibration damping of the boring bar. Moreover, when seen in a cross-sectional plane that is perpendicular to a longitudinal axis of the elongated body and intersecting the cutting edge in a radially outermost point, straight and imaginary first and second reference lines intersect the cutting edge in the radially outermost point with the first reference line extending at an angle of 6 to the relief surface on the outside of the cutting element, and the second reference line extending between the rake side and the relief surface at an angle of 10-40 to the first reference line. The actuator is arranged with its working axis extending in parallel with the second reference line.

A boring bar with electrodynamic actuators is for counteracting vibrations and machine tool provided with such a bar. The boring bar includes a wall, an internal recess and a longitudinal axis. The boring bar has a first electrodynamic actuator with coil windings associated with a moving mass and a spring assembly that are arranged to define a first actuation direction perpendicular to the longitudinal axis of the boring bar. A second electrodynamic actuator has coil windings associated with a moving mass and a spring assembly that are arranged to define a second actuation direction perpendicular to both the first actuation direction and the longitudinal axis of the boring bar. The actuators allow counteraction of the vibrations in the directions perpendicular to the longitudinal axis of the bar. The longitudinal axis also defines the boring direction.