Damper device

A damper device, comprising:

• a first rotor by which torque is input into the damper device and arranged to be rotated about a rotational axis;
• a second rotor by which torque is output from the damper device and arranged to be rotated about the rotational axis, the second rotor disposed to be rotatable relative to the first rotor in a first rotational direction and in a second rotational direction that is opposite to the first rotational direction;
• an elastic coupling part including a first elastic member and a second elastic member, the elastic coupling part configured to elastically couple the first and second rotors in said first and second rotational directions;
• and
• a hysteresis generating mechanism configured to generate a hysteresis torque when torsion is caused by rotation of the second rotor relative to the first rotor, the hysteresis generating mechanism including a friction member configured to cause friction by sliding relative to the first or the second rotor,
• wherein the friction member of the hysteresis generating mechanism does not cause friction by sliding relative to either the first rotor or the second rotor in a first torsion angular range extending from a neutral condition where there is no torsion between the first and second rotors to a first angular amount of relative rotation in the first rotational direction and to the first angular amount of relative rotation in the second rotational direction,
• the friction member causes friction by sliding relative to the first or second rotor so as to generate the hysteresis torque in a second torsion angular range exceeding the first torsion angular range in the first rotational direction or the second rotational direction,
• the friction member is further configured to be held in a neutral position by contact with and compression of the first and second elastic members when the first and second rotors are in the neutral condition,
• the first rotor includes a first support portion with a width in the circumferential direction of the first rotor and a second support portion with a width in the circumferential direction of the first rotor, and the second rotor includes a first accommodation portion with a width in the circumferential direction of the second rotor and a second accommodation portion with a width in the circumferential direction of the second rotor, the width of the first accommodation portion being the same as the width of the first support portion and the width of the second accommodation portion being the same as the width of the second support portion,
• the first accommodation portion is disposed to overlap in part the first support portion and to be angularly offset from the first support portion in the first rotational direction when the first and second rotors are in the neutral condition, and the second accommodation portion is disposed to overlap in part the second support portion and to be angularly offset from the second support portion in the second rotational direction when the first and second rotors are in the neutral condition, and
• the first elastic member is compressed in the first support portion and the first accommodation portion when the first and second rotors are in the neutral condition, and the second elastic member is compressed in the second support portion and the second accommodation portion when the first and second rotors are in the neutral condition, the second elastic member actuated in parallel with the first elastic member and expansionary forces within the first and second elastic members counteracting each other when the first and second rotors are in the neutral condition to hold the first and second rotors in the neutral condition and the friction member in the neutral position.