A vibration attenuator has a first spinner configured for rotation about a first axis and a first mass coupled to the first spinner for rotation therewith, the first mass being movable radially relative to the first axis between an inner position and an outer position. An actuator is coupled to the first mass for selectively controlling a radial location of the first mass relative to the axis, and a first motor is configured for driving the first spinner in rotation about the first axis.

To provide an electric motor enabling easy and high-precision balance correction, and a machine toll including this electric motor. An electric motor (1) includes: a cylindrical stator (2); a rotor (3) having a rotary shaft part (31) inserted inside of the stator (2); a housing (4) installed to both ends in an axial direction of the stator (2); an opening (51a) provided in at least one outer peripheral lateral face of the housing (4), and disposed to be separated from an internal space (S) of the stator and a ventilation passage (9) formed in the stator (2); and a balance correction component (6, 61) that is installed to the rotary shaft part (31), and corrects balance of the rotor (3), in which the balance correction component (61) is exposed to outside from the opening (51a); and a machine tool (10) includes this electric motor (1).

To provide an electric motor enabling easy and high-precision balance correction, and a machine toll including this electric motor. An electric motor (1) includes: a cylindrical stator (2); a rotor (3) having a rotary shaft part (31) inserted inside of the stator (2); a housing (4) installed to both ends in an axial direction of the stator (2); an opening (51a) provided in at least one outer peripheral lateral face of the housing (4), and disposed to be separated from an internal space (S) of the stator and a ventilation passage (9) formed in the stator (2); and a balance correction component (6, 61) that is installed to the rotary shaft part (31), and corrects balance of the rotor (3), in which the balance correction component (61) is exposed to outside from the opening (51a); and a machine tool (10) includes this electric motor (1).

The present disclosure provides vibratory compactor comprising an active isolation apparatus for reducing a vibration generated during the rotation of an eccentric shaft having an eccentric weight attached thereto. The active isolation apparatus comprises a drum, a propulsion motor configured to rotate the drum, a drive plate disposed between the propulsion motor and the drum in such a way as to be connected to the propulsion motor to transmit a rotating force to the drum, and a drum support configured to rotatably support the drum. The active isolation apparatus further comprises a first active isolation mass disposed between the drum support and the drum, a second active isolation mass disposed between the drive plate and the drum, an eccentric shaft configured to be rotated while penetrating through the first active isolation mass, the drum, and the second active isolation mass, a primary eccentric weight attached to the eccentric shaft inside the drum, an active isolation eccentric weight attached to each of the eccentric shaft inside the first active isolation mass and the second active isolation mass, and a vibration motor configured to rotate the eccentric shaft. In accordance with the active isolation apparatus of the present disclosure, when the eccentric shaft is rotated, a phase of a vibration generated by the active isolation eccentric weights is opposite to that of a vibration generated by the primary eccentric weight, and the vibration generated by the active isolation eccentric weights cancels the vibration generated by the primary eccentric weight.

The present disclosure provides vibratory compactor comprising an active isolation apparatus for reducing a vibration generated during the rotation of an eccentric shaft having an eccentric weight attached thereto. The active isolation apparatus comprises a drum, a propulsion motor configured to rotate the drum, a drive plate disposed between the propulsion motor and the drum in such a way as to be connected to the propulsion motor to transmit a rotating force to the drum, and a drum support configured to rotatably support the drum. The active isolation apparatus further comprises a first active isolation mass disposed between the drum support and the drum, a second active isolation mass disposed between the drive plate and the drum, an eccentric shaft configured to be rotated while penetrating through the first active isolation mass, the drum, and the second active isolation mass, a primary eccentric weight attached to the eccentric shaft inside the drum, an active isolation eccentric weight attached to each of the eccentric shaft inside the first active isolation mass and the second active isolation mass, and a vibration motor configured to rotate the eccentric shaft. In accordance with the active isolation apparatus of the present disclosure, when the eccentric shaft is rotated, a phase of a vibration generated by the active isolation eccentric weights is opposite to that of a vibration generated by the primary eccentric weight, and the vibration generated by the active isolation eccentric weights cancels the vibration generated by the primary eccentric weight.

A balance device for an internal combustion engine includes a crankshaft and a balance shaft. The crankshaft includes a CS eccentric weight. The balance shaft includes a BS eccentric weight. A CS connected point deviated from the CS main shaft, and a BS connected point deviated from the BS axial shaft are connected with a connection rod. A CS connection mechanism that enables relative rotation of the crankshaft and the connection rod is provided at the CS connected point. A BS connection mechanism that enables relative rotation of the balance shaft and the connection rod is provided at the BS connected point. A guide section guides a motion of the connection rod so that the balance shaft rotates in an opposite direction to the crankshaft.

An apparatus for vibration reduction in a linear actuator includes one or more sets of counterweights, one or more enclosures configured to receive one set of counterweights for each enclosure, and a driving shaft configured to mount the one or more sets of counterweights. The one or more sets of counterweights are disposed symmetrically with respect to a plane that extends perpendicularly and longitudinally through a longitudinal axis of the linear actuator. The driving shaft extends perpendicularly and transversely through the longitudinal axis and the plane. A portion counterweight of a given set of counterweights may rotate clockwise and another portion counterweight of the given set of counterweights may rotate counterclockwise.

An apparatus for vibration reduction in a linear actuator includes one or more sets of counterweights, one or more enclosures configured to receive one set of counterweights for each enclosure, and a driving shaft configured to mount the one or more sets of counterweights. The one or more sets of counterweights are disposed symmetrically with respect to a plane that extends perpendicularly and longitudinally through a longitudinal axis of the linear actuator. The driving shaft extends perpendicularly and transversely through the longitudinal axis and the plane. A portion counterweight of a given set of counterweights may rotate clockwise and another portion counterweight of the given set of counterweights may rotate counterclockwise.

A rotary wing aircraft including a vehicle vibration control system. The vehicle vibration control system includes a rotary wing aircraft member sensor for outputting rotary wing aircraft member data correlating to the relative rotation of the rotating rotary wing hub member rotating relative to the body, at least a first nonrotating body vibration sensor, the at least first nonrotating body vibration sensor outputting at least first nonrotating body vibration sensor data correlating to vibrations, at least a first nonrotating body circular force generator, the at least a first nonrotating body circular force generator fixedly coupled with the nonrotating body, the at least first nonrotating body circular force generator controlled to produce a rotating force with a controllable rotating force magnitude and a controllable rotating force phase, the controllable rotating force magnitude controlled from a minimal force magnitude up to a maximum force magnitude, and with the controllable rotating force phase controlled in reference to the rotary wing aircraft member sensor data correlating to the relative rotation of the rotating rotary wing hub rotating relative to the nonrotating body wherein the vibration sensed by the at least first nonrotating body vibration sensor is reduced.

A rotary wing aircraft including a vehicle vibration control system. The vehicle vibration control system includes a rotary wing aircraft member sensor for outputting rotary wing aircraft member data correlating to the relative rotation of the rotating rotary wing hub member rotating relative to the body, at least a first nonrotating body vibration sensor, the at least first nonrotating body vibration sensor outputting at least first nonrotating body vibration sensor data correlating to vibrations, at least a first nonrotating body circular force generator, the at least a first nonrotating body circular force generator fixedly coupled with the nonrotating body, the at least first nonrotating body circular force generator controlled to produce a rotating force with a controllable rotating force magnitude and a controllable rotating force phase, the controllable rotating force magnitude controlled from a minimal force magnitude up to a maximum force magnitude, and with the controllable rotating force phase controlled in reference to the rotary wing aircraft member sensor data correlating to the relative rotation of the rotating rotary wing hub rotating relative to the nonrotating body wherein the vibration sensed by the at least first nonrotating body vibration sensor is reduced.