A vibration absorber which, in addition to a main mass which is fixed thereto and moved along a curved trajectory by a driving mechanism, comprises a substantially smaller variably adjustable rotating flywheel mass which is moved together with the main mass along the trajectory thereof, enabling the adjustment of the frequency of the absorber. The rotating flywheel mass is driven by a novel belt device independently of the driving mechanism. A rotating vibration absorber which, along with the main mass and the rotating flywheel mass, comprises its own damping unit, such as an eddy-current damping unit.

A vibration absorber which, in addition to a main mass which is fixed thereto and moved along a curved trajectory by a driving mechanism, comprises a substantially smaller variably adjustable rotating flywheel mass which is moved together with the main mass along the trajectory thereof, enabling the adjustment of the frequency of the absorber. The rotating flywheel mass is driven by a novel belt device independently of the driving mechanism. A rotating vibration absorber which, along with the main mass and the rotating flywheel mass, comprises its own damping unit, such as an eddy-current damping unit.

A rolling vibration reduction device for an internal combustion engine includes: a main inertial system configured to rotate with a crankshaft of the internal combustion engine; a driving force transmission mechanism configured to transmit a rotational driving force of the crankshaft, a direction of the rotational driving force being reversed by the driving force transmission mechanism; and a sub-inertial system configured to rotate by the rotational driving force transmitted from the driving force transmission mechanism and to reduce rolling vibration of the internal combustion engine associated with rotation of the crankshaft by rotating in an opposite direction to the crankshaft. A torsional resonance frequency in the rolling vibration reduction device is set to a value higher than an explosion primary frequency at a maximum engine speed in a preset operating region of the internal combustion engine.

A coupling for transmitting torque from a drive to a load has a first connection for connection with the drive, a second connection for connection with the load, and an elastic element for vibration damping and between the first and second connections in the energy transmission path therebetween. An actuator carried on the elastic element has a base body and a centrifugal mass body rotatable relative thereto. One of the two bodies carries an electrical conductor and the other of the two bodies carries a permanent magnet. The conductor is in a magnetic field of the permanent magnet. Thus a flow of current through the conductor makes the centrifugal mass body exert an angular force on the base body to compensate for rotational vibrations.

A coupling for transmitting torque from a drive to a load has a first connection for connection with the drive, a second connection for connection with the load, and an elastic element for vibration damping and between the first and second connections in the energy transmission path therebetween. An actuator carried on the elastic element has a base body and a centrifugal mass body rotatable relative thereto. One of the two bodies carries an electrical conductor and the other of the two bodies carries a permanent magnet. The conductor is in a magnetic field of the permanent magnet. Thus a flow of current through the conductor makes the centrifugal mass body exert an angular force on the base body to compensate for rotational vibrations.

A vibration control device includes: a rotor formed of a soft magnetic body and fixed to an output shaft of a rotation driver or to a shaft that rotates in conjunction with the output shaft, the rotor being configured to rotate in response to rotation of the output shaft; a stator provided in a radial circumference of a rotation axis of the rotor; coils fixed to the stator and provided in a pair with the rotation axis therebetween; a charger-discharger provided in such a manner as to be connectable to the coils; a switching circuit provided capable of switching between connecting and disconnecting the coils and the charger-discharger; a first detector configured to detect a rotation angle of the rotor; and a control circuit configured to control operation of the switching circuit in accordance with the rotation angle of the rotor.

The invention includes systems having a cover attached to a frame, and a transmission unit with a rotational device connected to or part of the frame. The cover is mechanically connected to the at least one rotational device. A vibration dampening unit mechanically connected to the transmission unit such that translational movement (e.g. vertical movements) of the cover causes rotational movement of the rotational device. The rotational movement is, in turn, transmitted to the vibration dampening unit via the transmission unit. Preferably, the vibration dampening unit is a passive unit and also a resistance force modulated vibration dampening unit. The invention also includes methods for dampening vibrations on a load which includes converting translational movement of a load to rotational movement in a transmission unit, the transmission magnifies the displacement and speed of the rotational movement, and then transmitting the rotational movement to a vibration dampening unit, which dissipated the vibrational energy.

The invention includes systems having a cover attached to a frame, and a transmission unit with a rotational device connected to or part of the frame. The cover is mechanically connected to the at least one rotational device. A vibration dampening unit mechanically connected to the transmission unit such that translational movement (e.g. vertical movements) of the cover causes rotational movement of the rotational device. The rotational movement is, in turn, transmitted to the vibration dampening unit via the transmission unit. Preferably, the vibration dampening unit is a passive unit and also a resistance force modulated vibration dampening unit. The invention also includes methods for dampening vibrations on a load which includes converting translational movement of a load to rotational movement in a transmission unit, the transmission magnifies the displacement and speed of the rotational movement, and then transmitting the rotational movement to a vibration dampening unit, which dissipated the vibrational energy.

A hybrid drive includes an internal combustion engine, an electrical machine, at least one torsional vibration damper, and an electronic control unit. The torsional vibration damper is designed for optimal vibration damping during operation of the internal combustion engine with the full number of cylinders of the internal combustion engine switched-on in internal-combustion-engine mode. The electronic control unit is further designed such that, in purely electric-motor mode where no cylinders are switched on, the electrical machine simulates the cylinder-ignition-dependent torque excitations of the switched-off internal combustion engine substantially identically until the internal combustion engine is switched back on.

A vibration attenuator for a rotor of an aircraft has a first ring with an eccentric weight, a coaxial second ring with an eccentric weight, and a central ring coaxial with the first and second rings and located therebetween. A first post extends from the first ring toward the central ring and is received in a first arcuate groove formed on the central ring, whereas a second post extends from the second ring toward the central ring and is received in a second groove formed on the central ring. A motor is configured for driving the central ring in rotation about the axis relative to the motor. The grooves are equal in length, and a center of the first groove is located on an opposite side from a center of the second groove. Rotation of the central ring by the motor causes rotation of the first and second rings.