Abstract: A motor rotor includes a rotatable shaft, and a magnet structure mounted around the shaft. The magnet structure includes magnet pieces including a first magnet piece and a second magnet piece. The first magnet piece has a fracture surface facing the second magnet piece, and an outer surface forming a circumferential surface of the magnet structure. A surface roughness of the fracture surface is greater than a surface roughness of the outer surface of the first magnet piece.

Abstract: A motor rotor includes a shaft body, a cylindrical magnet covering an outer circumferential surface of the shaft body, a cylindrical protective layer covering an outer circumferential surface of the magnet and an annular end ring having the shaft body inserted therethrough, and in contact with an end surface of the magnet. The end ring is fixed to the shaft body by an inner circumferential resin portion formed between an inner circumferential surface of the end ring and the outer circumferential surface of the shaft body.

Abstract: A rotor includes a cylindrical magnet structure extending in an axial direction to cover a shaft, and a protective tube including a fiber body covering an outer circumferential surface of the magnet structure. The outer circumferential surface of the magnet structure has a first tapered surface gradually decreasing in diameter toward a first end surface of the magnet structure, and a second tapered surface gradually decreasing in diameter toward a second end surface opposite the first end surface in the axial direction. The protective tube includes a first end portion that is bonded to the first tapered surface of the magnet structure, and a second end portion that is bonded to the second tapered surface of the magnet structure.

Abstract: A friction stir welding device includes a friction stir welding tool equipped with a fixed shoulder on an outer periphery of a probe on a proximal end side, a main shaft positioning mechanism which relatively moves the friction stir welding tool with respect to a corner portion between workpieces a control device thereof, and a filler supply unit which supplies a filler to a stirring region in which the workpieces are stirred by the probe at the time of friction stir welding. When the probe is immersed into the corner portion to perform the friction stir welding, the fixed shoulder is maintained at a position separated by a gap from the surfaces of the workpieces with the control device.

Abstract: A friction stir welding device includes a pair of workpiece surface plates between which a gap extending along a welding line between workpieces is formed; a welding device body including a rotatable friction stir welding tool protruding upward from the gap; and a linear guide mechanism and a moving device for the welding device body. The moving device has a configuration in which a pair of pin racks extending in a direction along the gap are disposed at symmetrical positions on both sides in a width direction with a position immediately below a tool movement path of the friction stir welding tool as a symmetrical axis, and pin gears that individually mesh therewith are provided in the welding device body so as to be rotatably driven. Respective sets of a pin rack and a pin gear are alternately brought into a strong meshing state during the movement of the welding device body by causing the locations of pins and teeth thereof to deviate from each other by a half pitch.

Abstract: A friction stir welding device includes a friction stir welding tool equipped with a fixed shoulder on an outer periphery of a probe on a proximal end side, a main shaft positioning mechanism which relatively moves the friction stir welding tool with respect to a corner portion between workpieces a control device thereof, and a filler supply unit which supplies a filler to a stirring region in which the workpieces are stirred by the probe at the time of friction stir welding. When the probe is immersed into the corner portion to perform the friction stir welding, the fixed shoulder is maintained at a position separated by a gap from the surfaces of the workpieces with the control device.

Abstract: A friction stir welding device includes a pair of workpiece surface plates between which a gap extending along a welding line between workpieces is formed; a welding device body including a rotatable friction stir welding tool protruding upward from the gap; and a linear guide mechanism and a moving device for the welding device body. The moving device has a configuration in which a pair of pin racks extending in a direction along the gap are disposed at symmetrical positions on both sides in a width direction with a position immediately below a tool movement path of the friction stir welding tool as a symmetrical axis, and pin gears that individually mesh therewith are provided in the welding device body so as to be rotatably driven. Respective sets of a pin rack and a pin gear are alternately brought into a strong meshing state during the movement of the welding device body by causing the locations of pins and teeth thereof to deviate from each other by a half pitch.

Abstract: A workpiece securing device or a friction stir welding device is constituted of a starting-end-side workpiece stopper that positions a welding starting-end-side end of a workpiece to be placed on a workpiece surface plate; a finishing-end-side workpiece stopper that positions a welding finishing-end-side end of the workpiece; a starting-end-side workpiece clamping mechanism that presses and secures a portion along a welding line close to the welding starting-end-side end of the workpiece against the workpiece surface plate from above; and a finishing-end-side workpiece clamping mechanism that presses and secures a portion along the welding line close to the welding finishing-end-side end of the workpiece against the workpiece surface plate from above.

Abstract: A heating process makes a temperature of joining surfaces Wa and Ta of a pair of metal parts W and T at the start of a first joining process equal to 20% or greater, preferably, 40% or greater of a melting point of material of the metal parts W and T. The heating process makes a heating depth h of the pair of metal parts W and T at the start of the first joining process equal to 1.0 mm or greater.

Abstract: A heating process makes a temperature of joining surfaces Wa and Ta of a pair of metal parts W and T at the start of a first joining process equal to 20% or greater, preferably, 40% or greater of a melting point of material of the metal parts W and T. The heating process makes a heating depth h of the pair of metal parts W and T at the start of the first joining process equal to 1.0 mm or greater.

Abstract: In a friction stir welding apparatus, workpiece fixing surface plates (3a, 3b) are installed on a framework (1). In addition, a welding apparatus main body (8) including a bobbin tool (5) having a probe (5a) protruding upward from a gap (4), a spindle (6) configured to attach the bobbin tool (5) to an upper end section thereof, and a spindle driving apparatus (7) configured to pivot the spindle (6) is movably installed at the framework (1) in a longitudinal direction of the gap (4) via linear guide mechanisms (9) installed at both sides of the welding apparatus main body (8). Further, a moving apparatus (10) is installed to move the welding apparatus main body (8) in the longitudinal direction of the gap (4). According to the friction stir welding apparatus, since the welding apparatus main body (8) is supported by the framework (1) via both of the linear guide mechanisms (9), a large welding reaction force can be sufficiently received.

Abstract: A heating process makes a temperature of joining surfaces Wa and Ta of a pair of metal parts W and T at the start of a first joining process equal to 20% or greater, preferably, 40% or greater of a melting point of material of the metal parts W and T. The heating process makes a heating depth h of the pair of metal parts W and T at the start of the first joining process equal to 1.0 mm or greater.

Abstract: When a turbine impeller (4) formed from an Ni-based superalloy and a rotor shaft (2) formed from a steel material are joined by being fused together via welding in a boundary portion, a mixing ratio of a welding metal (6) that is formed in the boundary portion by fusing together the Ni-based superalloy forming the turbine impeller (4) and the steel material forming the rotor shaft (2) is between 0.5 and 0.8. As a result, it is possible to obtain a sound welding joint in which there are no cracks in the boundary between the welding metal (6) and the Ni-based superalloy (4).

Abstract: In a friction stir welding apparatus, workpiece fixing surface plates (3a, 3b) are installed on a framework (1). In addition, a welding apparatus main body (8) including a bobbin tool (5) having a probe (5a) protruding upward from a gap (4), a spindle (6) configured to attach the bobbin tool (5) to an upper end section thereof, and a spindle driving apparatus (7) configured to pivot the spindle (6) is movably installed at the framework (1) in a longitudinal direction of the gap (4) via linear guide mechanisms (9) installed at both sides of the welding apparatus main body (8). Further, a moving apparatus (10) is installed to move the welding apparatus main body (8) in the longitudinal direction of the gap (4). According to the friction stir welding apparatus, since the welding apparatus main body (8) is supported by the framework (1) via both of the linear guide mechanisms (9), a large welding reaction force can be sufficiently received.

Abstract: A Ni-based brazing composition at least containing, in mass %, 1.0% or more and 1.3% or less of B, 4.0% or more and 6.0% or less of Si, and the balance consisting of Ni and unavoidable impurities, wherein the brazing composition forms wherein the brazing composition forms dispersed phase containing B or Si in a metal texture after the brazing, and a maximum length of the dispersed phase is 30 ?m or less.

Abstract: A Ni-based brazing composition at least containing, in mass %, 1.0% or more and 1.3% or less of B, 4.0% or more and 6.0% or less of Si, and the balance consisting of Ni and unavoidable impurities, wherein the brazing composition forms wherein the brazing composition forms dispersed phase containing B or Si in a metal texture after the brazing, and a maximum length of the dispersed phase is 30 ?m or less.