HYDRAULIC POWER TRANSMISSION DEVICE

摘要

The purpose of the present invention is to achieve high damping performance stably over the entire normal rotational speed range with a simple structure in a hydraulic power transmission device including a dynamic damper. This device comprises a front cover (2), a torque converter body (8), a lockup device (6), and a dynamic damper (7). The dynamic damper (7) includes: a base plate (28); an inertia ring (29, 30) and a lid member (31, 32) that constitute an inertial body; a viscous damping part (33); and an elastic coupling part (34). The base plate (28) is fixed to an output plate (20). The inertial body is movable in the rotating direction relative to the base plate (28). The viscous damping part (33) is capable of generating a hysteresis torque that is variable in accordance with the relative speed difference between the base plate (28) and the inertial body.