Patent ID: 8391750

Claim:
A rotary driving device comprising: a rotary shaft supported rotatably about an axis thereof on a predetermined supporting member; a rotary load body mounted on the rotary shaft to project radially outward from the rotary shaft in such a manner that the rotary load body can rotate integrally with the rotary shaft about the axis thereof; a driver for rotating the rotary shaft about the axis thereof; a disk mounted on the rotary shaft coaxially therewith for integral rotation with the rotary shaft, the disk having a mounting hole formed therein, the mounting hole being aligned along a central axis set parallel to the axis of the rotary shaft; a pendulum loosely fitted in the mounting hole, the pendulum being caused to move radially outward within the mounting hole due to a centrifugal force produced by rotary motion of the disk on the rotary shaft; and an adjustment mechanism for adjusting a relative position relationship between a central axis position of the mounting hole and a center of gravity position of the pendulum under conditions where the pendulum is moved radially most outward in the mounting holes; wherein the disk has one and the other surfaces facing in opposite directions and has a cutout space formed therein by cutting out a portion of the disk from an outer peripheral surface thereof toward the mounting hole the pendulum is a truncated conical body having a tapered peripheral surface that has a diameter gradually decreasing from the one surface toward the other surface; and the adjustment mechanism goes into contact with the pendulum to regulate the amount of radially outward movement of the pendulum within the mounting hole, thereby adjusting the relative position relationship between the central axis position of the mounting hole and the center of gravity position of the pendulum, and includes an adjusting tab mounted in the cutout space and going into contact with the tapered peripheral surface of the truncated conical body and a moving member moving the adjusting tab back and forth along a thickness direction of the disk.