US 11,655,877 B2
Torsional vibration damper and manufacturing method thereof
Masayuki Ishibashi, Numazu (JP); Yu Shiraishi, Susono (JP); and Hiroyuki Amano, Susono (JP)
Assigned to Toyota Jidosha Kabushiki Kaisha, Toyota (JP)
Filed by Toyota Jidosha Kabushiki Kaisha, Toyota (JP)
Filed on Nov. 17, 2021, as Appl. No. 17/455,299.
Claims priority of application No. JP2020-204714 (JP), filed on Dec. 10, 2020.
Prior Publication US 2022/0186811 A1, Jun. 16, 2022
Int. Cl. F16F 15/14 (2006.01)
CPC F16F 15/145 (2013.01) [F16F 2222/08 (2013.01); F16F 2232/02 (2013.01); F16F 2236/08 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A torsional vibration damper comprising:
a rotary member that is rotated by torque transmitted thereto;
an inertia body that is arranged coaxially with the rotary member while being allowed to oscillate relatively to the rotary member;
a retainer having a pair of stoppers protruding radially outwardly from an outer circumference of the rotary member; and
a rolling mass that is held in the retainer to connect the rotary member to the inertia body while being allowed to reciprocate in a radial direction,
wherein torque of the rotary member is transmitted to the inertia body through the rolling mass to damp torsional vibrations of the rotary member,
the pair of stoppers are opposed to each other in a circumferential direction of the rotary member so that the rolling mass is held between the stoppers, and
a hardness of an inner surface of at least one of the stoppers is increased higher in a radially outer portion than in a radially inner portion, within a reciprocating range of the rolling mass.