| 摘要 |
PROBLEM TO BE SOLVED: To attach a flange while correctly aligning its axial center without needing a special non-conductive-layer-removal operation and without impairing the roundness of a cylindrical substrate, by freely turnably attaching a cutting tool to the end face of a flange on the engagement-part side by means of a shaft, and urging the cutting tool in a springing manner so that its blade projects further outside than the periphery of the flange. SOLUTION: In each of flanges 1, an engagement portion which engages with a cylindrical substrate 2 is formed in one end of an approximately cylindrical body, and a projection 5 or a gear 6 is formed on the periphery of the other end of it. In each flange 1, a cutting tool 7 is attached to its end face 1b which is inserted into the cylindrical substrate 2. The cutting tool 7 forms a sharp blade on one side of its leading end and is cuttable the internal face of the cylindrical substrate 2. In a position out of the central axis of the flange 1, the root of the cutting tool 7 is freely turnably attached with a pin. By means of a spring, the blade is urged so as to slightly project further outward than the periphery of the drum engagement portion of the flange 1, that is, in a radial direction. The blade is formed in the inside corner of the face of its leading end, that is, in a portion of the cutting tool 7 where it and the side wall of the flange on the axial center side join. |
