Patent ID: 6308810
Filing Date: 2001-10-30
Classification: F16F

Abstract:
A dynamic damper for damping vibration of a rotary shaft, comprising:a mass member having a generally cylindrical shape and formed from a plate having a predetermined contour, said plate being rolled into said generally cylindrical shape and including circumferentially opposite end portions which are opposed to each other in a circumferential direction thereof and which are unconnected to each other;an elastic support member to be mounted on said rotary shaft, for elastically supporting said mass member with respect to said rotary shaft such that said mass member is displaceable relative to said rotary shaft; andbalancing means for maintaining a rotary balance of said mass member about an axis of said mass member,wherein said circumferentially opposed end portions of said plate have respective end faces which are spaced apart from each other with a circumferential gap in said circumferential direction, and wherein said balancing means cooperates with said circumferential gap to maintain said rotary balance of said mass member about said axis, said balancing means comprising at least one of mass-reducing means for reducing a mass of a circumferentially central portion of said plate which is substantially diametrically opposed to said circumferential gap, and mass-increasing means for increasing a mass of said circumferentially opposite end portions of said plate.