| 摘要 |
PROBLEM TO BE SOLVED: To obtain more vibration quantity by fitting an eccentric weight to a rotary shaft without forming a projected rotary shaft fitting base part causing the reduction of vibration quantity on an eccentric weight face formed in a counter gravity center direction. SOLUTION: A rotary shaft fitting groove 6 having a semicircular shape at the time of observing it from an axial direction is formed on the center part of a rotational trace of an eccentric weight 3 without forming a vibration quantity reducing projection such as a rotary shaft fitting base part on the face 9 of the weight 3 which is opposite side to the gravity center G direction. Plural fine projections 7 are formed on the inner surface 8 of the groove 6. The rotary shaft 2 is brought into contact with the groove 6 and the fine projections 7 are deposited from the surface of the shaft 2, so that the shaft 2 can be welded and fixed on the inner surface 8 of the groove 6. |
