A method for controlling an elastic mount configured to support a propulsion device with respect to a marine vessel, wherein the elastic mount contains an electromagnetic fluid and an electromagnet and is configured such that adjusting an amount of electricity applied to the electromagnet changes the shear strength of the electromagnetic fluid and thereby controls elasticity of the elastic mount, including applying a first amount of electricity to the electromagnet to produce a first elasticity in the elastic mount, determining that a vessel speed indicator exceeds a high speed threshold, determining that a trim position for the propulsion device is greater than a threshold trim position, detecting at least a threshold decrease in throttle demand, and applying a second amount of electricity to the electromagnet wherein the second amount of electricity is greater than the first amount of electricity, so as to decrease the elasticity of the elastic mount.

A variable stiffness vibration damping device includes a first support member, a second support member, a main elastic member, a diaphragm, a partition elastic member, a first communication passage, a coil, a yoke, and a magnetic fluid. The first communication passage is provided in one of the first support member and the second support member such that a first liquid chamber and a second liquid chamber communicate with each other via the first communication passage. The first communication passage includes a first circumferential passage. The coil is wound coaxially with the one of the first support member and the second support member. The yoke is included in the one of the first support member and the second support member and forms a first magnetic gap overlapping at least partially with the first circumferential passage.

A method for controlling an elastic mount configured to support a propulsion device with respect to a marine vessel, wherein the elastic mount contains an electromagnetic fluid and an electromagnet and is configured such that adjusting an amount of electricity applied to the electromagnet changes a shear strength of the electromagnetic fluid in the elastic mount and thereby controls an elasticity of the elastic mount. The method includes applying a first amount of electricity to the electromagnet to produce an initial elasticity of the elastic mount measuring an oscillation of the propulsion device with a motion sensor, determining that the oscillation of the propulsion device exceeds a threshold oscillation, and adjusting the amount of electricity applied to the electromagnet to change the elasticity of the elastic mount to reduce the oscillation.

A top mount assembly including a housing for being connected to the frame of the vehicle. A rod connection assembly is disposed in the housing for being attached to a piston rod of the damper assembly. A chamber is defined between the rod connection assembly and the housing for receiving a fluid. A resilient member is disposed between the rod connection assembly and the housing. A partition assembly is positioned between the resilient member and the housing and axially divides the chamber into an upper chamber region and a lower chamber region. The partition assembly defines at least one passage that extends between the upper chamber region and the lower chamber region. At least one electromagnetic coil is disposed adjacent to the passage for selectively modifying the characteristics of the fluid passing through the passage to modify the damping characteristics of the top mount assembly.

A hydraulic mount assembly includes a mount body defining a cavity. A powertrain includes a dynamic mass, and a structure that supports the dynamic mass. The assembly is attached to the structure and supports the dynamic mass. A first plate is fixed relative to the mount body inside the cavity to separate the cavity into a first chamber and a second chamber. The first plate defines a plurality of first passages that fluidly connects the first and second chambers. A decoupler is disposed between the first and second chambers. An actuator is coupled to the first plate. The decoupler is movable in response to actuation of the actuator. The decoupler abuts the first plate when in a locked position to prevent fluid communication through the first passages. The decoupler is movable relative to the first plate when in an unlocked position to allow fluid communication through the first passages.

A vibration isolating device is provided. An inner shaft member and an outer tube member are connected to each other with a main body rubber elastic body and plural fluid chambers filled with a fluid are provided to be separated from each other in a circumferential direction and communicates with each other through an orifice passage. The fluid is a magnetically functional fluid. The outer tube member is a non-magnetic material. A tubular cover member is disposed to be separated toward an outer circumferential side from the outer tube member. A magnetic field generating unit exerting a magnetic field on the magnetically functional fluid is assembled between the outer tube member and the tubular cover member. One side member and another side member to be connected to each other in a vibration isolating manner are configured to be attached to the inner shaft member and the tubular cover member.

A variable stiffness bushing includes: inner and outer tubular members; and an elastic member connecting these tubular members. At least one pair of liquid chambers axially separated from each other is defined in the elastic member. The liquid chambers are connected by a communication passage including a circumferential passage provided in one of the inner and outer tubular members. The one of the inner and outer tubular members includes a coil wound coaxially therewith and a yoke provided with a gap constituting the circumferential passage. A magnetic fluid fills the liquid chambers and the communication passage. Upper and lower end walls and an axially intermediate partition wall of the elastic member are configured such that when the tubular members are axially displaced relative to each other, a difference is created between volumes of the axially separated liquid chambers.

A mount bush includes a tubular member, a shaft member disposed inside the tubular member coaxially with an axis of the tubular member and including a coil, a permanent magnet provided on at least one of the tubular member and the shaft member, a magnetic viscoelastic fluid filled in an internal space, a first liquid chamber disposed in the internal space at a first side, a second liquid chamber communicating with the first liquid chamber, and a third liquid chamber communicating with the second liquid chamber, wherein the coil is disposed such that a magnetic path passing through the second liquid chamber in an orientation along at least one of the axial direction and the radial direction perpendicular to the axial direction is formed through electrical conduction, and the permanent magnet is disposed such that a magnetizing direction is formed along the magnetic path.

A mount bush includes: an inner tubular member; an outer tubular member arranged coaxially with the inner tubular member and surrounding an outer periphery of the inner tubular member with a clearance; and an elastic member connecting the inner tubular member with the outer tubular member, wherein the inner tubular member includes: an inner yoke having a coil therein; and an outer yoke coaxially coupled with the inner yoke at a radially outer position than the coil, and the elastic member has a first and second fluid chambers, facing each other across an axis of the inner tubular member and having magnetic fluid encapsulated therein, whose viscosity varies by a magnetic field, wherein the outer yoke has a communication passage communicating the first fluid chamber with the second fluid chamber, and is provided with a permanent magnet to generate a magnetic field in the communication passage.

A variable stiffness bushing assembly includes an inner tubular member, an outer tubular member coaxially surrounding the inner tubular member, and an elastic member connecting the inner and outer tubular members. The elastic member defines a pair of first liquid chambers that are on opposite sides of an axial line of the inner tubular member and communicate with each other via a first circumferentially extending communication passage defined between one of the outer yokes and the annular large diameter portion, and a pair of second liquid chambers that are on opposite sides of the axial line and communicate with each other via a second circumferentially extending communication passage defined between another one of the outer yokes and the annular large diameter portion. The magnetic fields generated by the two coils are selectively applied to a magnetic fluid flowing through the first communication passage and the second communication passage.