Patent ID: 7946925

Claim:
A dynamic damper for damping vibrations of a rotational shaft, comprising: a substantially cylindrical main body having a through hole in which said rotational shaft is press-fitted; a mass portion containing a weight, disposed radially outwardly of said main body in the vicinity of one axial direction end of said main body; a flexible annular joint support disposed between said main body and said mass portion; and a band which is tightened on a portion of said main body in the vicinity of another axial direction end of said main body to fix said main body to said rotational shaft, said portion not overlapping with said mass portion in a radial direction, wherein, when D 1 represents an outer diameter of said rotational shaft, D 2 represents an inner diameter of said through hole at said one axial direction end of said main body where said mass portion is disposed outwardly, and D 3 represents an inner diameter of said through hole at said other axial direction end of said main body where said mass portion is not disposed outwardly, said outer diameter D 1 , said inner diameter D 2 , and said inner diameter D 3 satisfy respective relational expressions of D 1 >D 2 , and D 1 >D 3 >D 2 .