In a roughing end mill, an end mill main body is provided with: a peripheral cutting edge; an end cutting edge; and a corner cutting edge formed between the peripheral cutting edge and the end cutting edge. A roughing part having a waveform pattern of recesses and protrusions is formed in the peripheral cutting edge, and a phase of the recesses and protrusions of the roughing part of one chip discharge flute is shifted with respect to that of the other chip discharge flute adjacent to the one chip discharge flute. A foremost protrusion of the roughing part of one peripheral cutting edge is located closer to a distal end of the end mill main body than those of the other peripheral cutting edges, a peak of the foremost protrusion of the one peripheral cutting edge is aligned with another peak of the corner cutting edge adjacent to the one peripheral cutting edge. Also, a peak of a foremost protrusion of the roughing part of each of the other peripheral cutting edges is connected to another peak of the corner cutting edge adjacent to the other peripheral cutting edge by another straight portion extending in a linear manner.

A tool chuck for clamping a tool in a machine tool, having a base body and a sleeve part protruding therefrom, which sleeve part forms a tool holder for fixing a tool shaft in a frictional, nonpositive fashion; a cavity in which a vibration damping component is accommodated is provided in the tool chuck.

A side milling cutter for slot cutting is provided whose vibration can be damped even in cases where a vibration mode of the cutter generates plural nodes in a cutting part. A side milling cutter for slot cutting of the present invention includes a disc-shaped cutter and a plurality of cartridges as cutting edges provided at a predefined interval in a circumferential direction along an outer circumference of the disc-shaped cutter. The disc-shaped cutter cuts a predefined slot on a workpiece using the cartridges by circumferentially rotating. The disc-shaped cutter internally includes a plurality of vibration damping structures in the circumferential direction on a disk surface of the disc-shaped cutter.

A roughing end mill includes: an end mill main body rotated about an axis; and four or more of outer peripheral cutting edges provided on an outer circumference of a tip part of the end mill main body spaced apart in a circumferential direction, each of the outer peripheral cutting edges extending from a tip of the end mill main body to a rear side, wherein each of outer peripheral cutting edges includes a waveform cutting edge that is concaved and convexed in a radial direction, a phase is shifted within one pitch, and the waveform cutting edges of the outer peripheral cutting edges have one or more parts, in which phases of the waveform cutting edges are sequentially shifted multiple times toward a rear end side of the end mill main body, and shifted the same multiple times toward a tip end side of the end mill main body.

Provided is a vibration-proof structure capable of more effectively reducing rotational vibration of a rotating body during a cutting operation. According to a configuration of the structure, inside a main body of the rotating body, there are provided a plurality of shaft members arranged along a longitudinal direction of a rotation axis of the rotating body and at least one layer of multiple tubular members fitted over the shaft members and arranged coaxially with the rotation axis along the longitudinal direction of this rotation axis; and a boundary position between the shaft members adjacent each other in the longitudinal direction and a boundary position between the tubular members adjacent each other in the longitudinal direction are set as different positions along the longitudinal direction.

The invention relates to a method for reducing regenerative chatter in that a workpiece (1) rotates in relation to a tool head (2) having at least one chip-removal tool (3, 3a, 3b, 3c) arranged at one end of the tool head (2), the tool head (2) machines walls of the workpiece (1) by means of the at least one chip-removal tool (3, 3a, 3b, 3c), the tool head (2) is vibrationally excited during the machining, a loose additional mass (m.sub.z) is moved by the vibration, which additional mass randomly touches the tool head (2) in first positions or randomly has no connection to the tool head (2) in second positions, and thus the total mass of the tool head (2) is randomly changed by the amount of the additional mass (m.sub.z).

A tool chuck for clamping a tool in a machine tool, having a base body and a sleeve part protruding therefrom, which sleeve part forms a tool holder for fixing a tool shaft in a frictional, nonpositive fashion; a cavity in which a vibration damping component is accommodated is provided in the tool chuck.

A damper device for a machine tool, the damper device comprising a tubular element having a cavity and a central axis, the tubular element comprising a first surface; a damping mass arranged within the cavity and movable radially with respect to the central axis and relative to the tubular element; at least one spring element supporting the damping mass relative to the tubular element, the damping mass and the at least one spring element being arranged to attenuate kinetic vibration energy of the damper device; at least one fixed part having a fixed interior portion inside the cavity and a second surface; and a vibration damping material provided between the first surface and the second surface, the vibration damping material being arranged to attenuate potential vibration energy of the damper device; wherein the vibration damping material is substantially evenly compressed between the first surface and the second surface.

A tool for machining work pieces is disclosed. In order to provide a tool which exhibits only very small vibrations during operation, the tool body of the tool has a cavity in which a multiplicity of hollow structural elements having an outer closed shell, within which at least one solid particle or a hollow body is arranged in a freely movable manner, are accommodated.

A rotary cutting tool has a central, longitudinal axis. One or more internal balancing features are disposed within a cavity of the rotary cutting tool. Each internal balancing feature includes a balancing mass suspended within the cavity by a spring-like element, and an adjusting screw for effecting radial movement of the balancing mass. Each internal balancing feature can be integrally-formed with the rotary cutting tool using a 3-D printing technique. The rotary cutting tool can be any rotary cutting tool, such as a milling cutter, a boring bar, and the like. The internal balancing features are arranged at predetermined locations within the rotary cutting tool to enable static and/or dynamic balancing of the rotary cutting tool.