The method includes a preprocessing transfer step which places an unprocessed rod-like body in a receiving position; a post-processing transfer step which pushes a processed rod-like body with the unprocessed rod-like body, and thus transfers the processed rod-like body to a rail portion; a rail portion transfer step which pushes the processed rod-like body with the unprocessed rod-like body, and thus transfers the processed rod-like body while being guided by the rail portion; a withdrawing step which withdraws the processed rod-like body from the rail portion using a withdrawing unit; a detection step which detects that the processed rod-like body is transferred from the rail portion to the withdrawing unit; and a discharge step which discharges the processed rod-like body from the withdrawing unit in a direction perpendicular to an axis of the processed rod-like body.

A powder production method includes providing an elongated workpiece and repeatedly contacting an outer surface of the elongated workpiece with a reciprocating cutter according to a predetermined at least one frequency to produce a powder. The powder includes a plurality of particles, wherein at least 95% of the produced particles have a diameter or maximum dimension ranging from about 10 m to about 200 m. A system for producing powders having a plurality of particles including a cutter and at least one controller is also provided herein.

A powder production method includes providing an elongated workpiece and repeatedly contacting an outer surface of the elongated workpiece with a reciprocating cutter according to a predetermined at least one frequency to produce a powder. The powder includes a plurality of particles, wherein at least 95% of the produced particles have a diameter or maximum dimension ranging from about 10 m to about 200 m. A system for producing powders having a plurality of particles including a cutter and at least one controller is also provided herein.

A differential device including a planetary gear mechanism having a sub-gear, an annular gear and a planetary gear is more compact than a differential gear using a bevel gear mechanism. Since revolution torque of the planetary gear is transmitted to a free gear, and torque from the main gear is reduced to be transmitted, the differential device can use a small-sized drive unit in comparison with a conventional one. Hence, a machining apparatus including such a differential device is also compact. If the machining apparatus has three drive units, a pair of ring gears, first and second power transmission shafts, a radial movement mechanism and an axial movement mechanism, a tool holder, namely, a tool coupled to the radial movement mechanism and the axial movement mechanism, can be freely moved in axial and radial directions with respect to the pipe.

A differential device including a planetary gear mechanism having a sub-gear, an annular gear and a planetary gear is more compact than a differential gear using a bevel gear mechanism. Since revolution torque of the planetary gear is transmitted to a free gear, and torque from the main gear is reduced to be transmitted, the differential device can use a small-sized drive unit in comparison with a conventional one. Hence, a machining apparatus including such a differential device is also compact. If the machining apparatus has three drive units, a pair of ring gears, first and second power transmission shafts, a radial movement mechanism and an axial movement mechanism, a tool holder, namely, a tool coupled to the radial movement mechanism and the axial movement mechanism, can be freely moved in axial and radial directions with respect to the pipe.

A cutting tool 1 includes a cutting edge 2, a rake face 4 and a flank 5 and is used for cutting a surface of a cylindrical or columnar work W by a skiving process. The cutting tool 1 is configured to satisfy a relational expression:

tan.sup.1(cos /cos()tan.sup.1(cos.sup.1(r/r))<90

where denotes a rake angle, denotes an inclination angle of the cutting edge 2 with respect to the rotation axis A, denotes an angle between a feed direction of the cutting tool 1 and a direction orthogonal to a rotation axis A in a plane view of the cutting tool 1 and the work W, r denotes a radius of an outer circumferential surface of the work W before processing, and r denotes the radius of the outer circumferential surface of the work W after processing.

A cutting tool 1 includes a cutting edge 2, a rake face 4 and a flank 5 and is used for cutting a surface of a cylindrical or columnar work W by a skiving process. The cutting tool 1 is configured to satisfy a relational expression:

tan.sup.1(cos /cos()tan.sup.1(cos.sup.1(r/r))<90

where denotes a rake angle, denotes an inclination angle of the cutting edge 2 with respect to the rotation axis A, denotes an angle between a feed direction of the cutting tool 1 and a direction orthogonal to a rotation axis A in a plane view of the cutting tool 1 and the work W, r denotes a radius of an outer circumferential surface of the work W before processing, and r denotes the radius of the outer circumferential surface of the work W after processing.

An additive manufacturing head includes: a nozzle configured to discharge material powder; a rotary member connected with the nozzle, including a first material powder passage formed in the rotary member to direct the material powder to the nozzle, and configured to rotate to cause the nozzle to move in the circumferential direction about a laser beam emitted toward the workpiece; and a stationary member including a second material powder passage which is formed in the stationary member and into which the material powder is introduced, the stationary member being disposed directly beside the rotary member in the direction of the rotational axis of the rotary member. A third material powder passage communicating with the first material powder passage and the second material powder passage and extending annularly about the rotational axis of the rotary member is formed between the stationary member and the rotary member. Accordingly, an additive manufacturing head that implements a mechanism configured simply to feed material powder to an infinitely revolving nozzle is provided.

An apparatus for cutting pipes internally includes at least one cutting member, at least one drive member, at least one feed member, and at least one clamping member. The at least one cutting member cuts a pipe internally. The at least one drive member rotates the at least one cutting member to cut the pipe internally. The at least one feed member extend the at least one cutting member against the pipe internally and retracts the at least one cutting member from the pipe internally. The at least one clamping member secures the apparatus to the pipe internally.

A method and a device for machining a workpiece rotating about a rotational axis. The machining point moves along the cutting edge of a cutting edge plane and the surface to be machined in a rolling movement on an advancement plane not intersected by the rotational axis. A pivot drive implements a large enough pivot angle so that a first workpiece surface is machined by a machining point moving along the first cutting edge in a first machining step. In a second machining step, a second workpiece surface is machined, wherein the machining point moves along the second cutting edge and the second workpiece surface. The cutting edge has a curvature radius smaller than the distance from the pivot axis of the holder to the cutting edge. The holder can additionally be displaced on the advancement plane with a movement component in a direction transverse to the rotational axis.