A cutting insert comprising a cutting tip and a base insert on which the cutting tip is mounted, the cutting insert being provided with a passage PA which is formed along a boundary surface between the cutting tip and the base insert so as to extend from a boundary part, in an upper surface of the cutting insert, between the cutting tip and the base insert to another boundary part, in a lower surface of the cutting insert, between the cutting tip and the base insert.

A round double-sided cutting insert includes an insert peripheral surface that includes a plurality of angularly spaced apart indexing latches protruding therefrom and a plurality of cylindrical insert side abutment surfaces that circumferentially alternate with the plurality of indexing latches. An insert holder has a pocket peripheral surface which includes at least one indexing gap and a plurality of pocket side abutment surfaces that circumferentially alternate with the at least one indexing gap. When the cutting insert is releasably attached to the insert holder, to constitute a fastened position of a cutting tool, each of the plurality of pocket side abutment surfaces abuts a respective insert side abutment surface and each indexing gap has a respective indexing latch located therein.

A round double-sided cutting insert includes an insert peripheral surface that includes a plurality of angularly spaced apart indexing latches protruding therefrom and a plurality of cylindrical insert side abutment surfaces that circumferentially alternate with the plurality of indexing latches. An insert holder has a pocket peripheral surface which includes at least one indexing gap and a plurality of pocket side abutment surfaces that circumferentially alternate with the at least one indexing gap. When the cutting insert is releasably attached to the insert holder, to constitute a fastened position of a cutting tool, each of the plurality of pocket side abutment surfaces abuts a respective insert side abutment surface and each indexing gap has a respective indexing latch located therein.

A rotating tool is held in a tool holder. The tool holder includes a male tapered portion. The tool holder is rotated by a rotating-tool main shaft. The rotating-tool main shaft includes a hollow main shaft. The hollow main shaft includes a circular conical hole formed in a tip and corresponding to the male tapered portion. The hollow main shaft includes a fluid passage to detect that the male tapered portion is properly attached to the circular conical hole, and an opening to blow out a fluid. The opening is provided in a portion offset from the circular conical hole.

A control apparatus for machine tool, in accordance with user set conditions, feeds a cutting tool in a feeding direction while reciprocatively vibrating the cutting tool, smoothly cuts a workpiece, and achieves a machined surface having an improved appearance. In a machine tool and a control apparatus thereof, a control means is configured to set the number of rotations of relative rotation and the number of vibrations of reciprocating vibration during one rotation of the relative rotation in accordance with a vibration frequency attributable to a cycle during which an operation instruction can be issued, and the control means includes adjusting means configured to adjust the number of rotations or the number of vibrations set by the control means.

A control device for a machine tool and a machine tool, for which settings of the number of vibrations per rotation become easy, is provided. The control device of the machine tool controls a relative rotation between a workpiece and a cutting tool and a relative reciprocal movement between the workpiece and the cutting tool in a feed direction to perform vibration cutting to the workpiece. The control device includes a control section for controlling a spindle headstock, a first tool post, and a second tool post, the workpiece W being installed on the spindle headstock, the first tool post being provided to be reciprocally movable along the feed direction with respect to the spindle headstock and installed with a first cutting tool for cutting the workpiece, and the second tool post being provided to be reciprocally movable along the feed direction with respect to the spindle headstock independently of the first tool post and installed with a second cutting tool for cutting the workpiece.

A modulating tool holder includes a tool holder first end and a tool holder second end, and a central axis extending between the tool holder first end and the tool holder second end. The tool holder first end has a coupler for coupling the tool holder to a drive member of a machining device and the second end includes a clamp for releasably holding either a tool or a workpiece. A rotatable spindle member extends axially in the tool holder and imparts a rotational movement to the clamp. A central fluid passageway extends between first and second ends of the rotatable spindle member for conveying a fluid. A linear actuator is configured to impart an oscillating movement to the clamp. The linear actuator is functionally decoupled from the torsional load of the rotatable spindle member.

A cutting tool includes a shaft, and a sensor device disposed in such a manner as to surround a portion of the shaft. The sensor device includes a sensor module including first sensors, a substrate connected to the first sensors, and a wireless communication unit connected to the substrate and configured to transmit a signal including information detected by the first sensors to outside and a housing accommodating the sensor module. A region of the shaft surrounded by the sensor device includes a first region having a shape of a 4n-sided polygon when viewed from a direction in which the rotation axis extends. The plurality of first sensors are arranged on at least two of outer peripheral surfaces of the first region, perpendicular lines of the outer peripheral surfaces passing through the rotation axis and intersecting at 90 degrees.

A cutting tool includes a shaft, and a sensor device disposed in such a manner as to surround a portion of the shaft. The sensor device includes a sensor module including first sensors, a substrate connected to the first sensors, and a wireless communication unit connected to the substrate and configured to transmit a signal including information detected by the first sensors to outside and a housing accommodating the sensor module. A region of the shaft surrounded by the sensor device includes a first region having a shape of a 4n-sided polygon when viewed from a direction in which the rotation axis extends. The plurality of first sensors are arranged on at least two of outer peripheral surfaces of the first region, perpendicular lines of the outer peripheral surfaces passing through the rotation axis and intersecting at 90 degrees.

A method and a device applying surface structuring to a surface of a workpiece on a machine tool, performing a feed motion of a milling cutter which is rotationally driven by a work spindle of the machine tool, received in a tool head of the machine tool and has at least one protruding cutting edge along the surface of the workpiece; applying the surface structuring in accordance with a predetermined pattern to the surface of the workpiece during the feed motion of the milling cutter on the basis of a control signal to an actuator which is integrated in the tool head and is configured to drive a vibration of the milling cutter on the basis of the control signal, wherein the control signal contains high-frequency carrier signal and a useful signal which modulates the carrier signal and which is generated on the basis of data indicating the predetermined pattern.