Patent ID: 8562446
Filing Date: 2013-10-22
Classification: F16F

Abstract:
1. A torsion vibration damping apparatus, comprising: a hub member having a hub flange formed with a plurality of projection portions radially extending and circumferentially spaced apart from one another through recesses, a rotation member coaxially provided and relatively rotatable with the hub member, and formed with accommodation holes positioned in opposing relationship with the recesses, respectively, a plurality of resilient members respectively arranged in the recesses and the accommodation holes, and resiliently deformable to establish a torque transmission between the hub member and the rotation member when the hub member is circumferentially rotated in its positive and negative sides relatively with respect to the rotation member from its neutral position in which the hub member is not rotated relatively with respect to the rotation member, and a stopper portion provided on the rotation member to be positioned on the rotation path of each projection portion of the plurality of projection portions, and engageable with circumferential side surfaces of each projection portion to regulate the relative rotation of the hub member and the rotation member when the hub member is rotated in the positive and negative sides relatively with respect to the rotation member, each projection portion being formed with a projection amount circumferentially projected in the positive side from the radially center axis of each projection portion being smaller than a projection amount circumferentially projected in the negative side from the radially center axis of each projection portion so as to be in asymmetrical shape across the radially center axis, and a distance between a positive circumferential side surface of each projection portion and the stopper portion being longer than a distance between a negative side circumferential side surface of each projection portion and the stopper portion when the hub member and the rotation member are in respective neutral positions.