A laser welding apparatus (1) includes a laser welding head (5) configured to irradiate a workpiece (10) with laser light, a welding filler feeding mechanism (6) configured to supply a welding material to a position on which laser welding is performed, and a hollow structural moving mechanism (100) configured to move a welding unit (50) including the laser welding head and the welding filler feeding mechanism. The hollow structural moving mechanism has an insertion portion (3a) through which wire materials (41 and 62) of the laser welding head and the welding filler feeding mechanism are inserted.

A tapered roller bearing assembly includes a one-piece inner ring that has two outer raceways oriented at angles relative to a longitudinal axis and a first outer ring with a first inner raceway and a second outer ring having a second inner raceway. The bearing assembly includes a spacer ring that has an axial width and is positioned around the inner ring and between the first and outer rings. A plurality of rolling elements is in rolling engagement with the first outer raceway and the first inner raceway. A plurality of rolling elements is in rolling engagement with the second outer raceway and the second inner raceway. The axial width is selectively established to obtain a predetermined axial clearance between the inner ring and the first outer ring and the second outer ring.

A double row tapered roller bearing includes: an outer ring having an annular shape; an inner ring disposed on an inner circumferential side of the outer ring and having an annular shape; and rollers. The inner ring has an outer circumferential surface facing the outer ring and having two rows of grooves having a bottom surface serving as a raceway surface. The rollers are tapered rollers disposed in the grooves in contact with the raceway surface of the inner ring and are also in contact with the outer ring. At outer circumferential surface of the inner ring, a region adjacent to the groove includes a hardened region extending from the inner peripheral surface of the groove to the region adjacent to the groove, and an unhardened region located at a position farther from the groove than the hardened region and being smaller in hardness than the hardened region.

A speed change device comprising an inner race having an outer surface, an outer race having an inner surface, and set of orbital rollers including inner rollers in rolling contact with the outer surface of the inner race and outer rollers in rolling contact with the inner surface of the outer race.

A double row tapered roller bearing includes: an outer ring having an annular shape; an inner ring disposed on an inner circumferential side of the outer ring and having an annular shape; and rollers. The inner ring has an outer circumferential surface facing the outer ring and having two rows of grooves having a bottom surface serving as a raceway surface. The rollers are tapered rollers disposed in the grooves in contact with the raceway surface of the inner ring and are also in contact with the outer ring. At outer circumferential surface of the inner ring, a region adjacent to the groove includes a hardened region extending from the inner peripheral surface of the groove to the region adjacent to the groove, and an unhardened region located at a position farther from the groove than the hardened region and being smaller in hardness than the hardened region.

A roller of a support arrangement for a rotary milking platform, where the support arrangement includes a first rail member fixedly connected to the rotary platform, a second rail member stationarily arranged in a position below the platform, and a plurality of rollers arranged in a vertical space between the first rail member and the second rail member. Each roller includes a peripheral surface comprising a contact surface to be in contact with a contact portion of the first rail member and a contact portion of the second rail member. The peripheral surface of the roller includes two beveled surfaces arranged at opposite sides of the contact surface which are located at a smaller distance from a rotary axis of the roller than the contact surface.

A roller circle assembly for heavy machinery includes an upper circular rail and a lower circular rail concentrically arranged about a central axis, and tapered rollers between the upper and lower rail. Each tapered roller includes a flange having an angled and convex flange contact surface that contacts the lower rail. The lower rail and/or the upper rail can include an angled surface configured for contact with the flange contact surface. The geometry of the rollers and the lower rail are configured to reduce the stresses applied to the rollers and lower rail due to contact between the flange contact surface and the angled surface.

A roller of a support arrangement for a rotary milking platform, where the support arrangement includes a first rail member fixedly connected to the rotary platform, a second rail member stationarily arranged in a position below the platform, and a plurality of rollers arranged in a vertical space between the first rail member and the second rail member. Each roller includes a peripheral surface comprising a contact surface to be in contact with a contact portion of the first rail member and a contact portion of the second rail member. The peripheral surface of the roller includes two beveled surfaces arranged at opposite sides of the contact surface which are located at a smaller distance from a rotary axis of the roller than the contact surface.