Abstract: In an active vibration isolation support system in which internal pressures of fluid chambers whose volumes are changed by a load applied from outside are controlled by an actuator that reciprocatingly vibrates a movable core on an axis by energizing a coil cylindrically wound around an outer periphery of a fixed core, an end surface of the coil on the fluid chambers side is inclined so that a radially outer side of the end surface is close to the fluid chambers with respect to the axis. Therefore, the output can be increased by increasing the number of windings of the coil without increasing the dimension of the active vibration isolation support system in the direction of the axis.

Abstract: An active antivibration device which includes a main body, a mobile element which is elastically supported inside the main body and movable in an axial direction of the main body, and a coil which is disposed inside the main body and fixed to the main body. The mobile element includes a mobile axis body supported in the axial direction of the main body, and a first yoke, a permanent magnet and a second yoke which are held by the mobile axis body and disposed successively along an axial direction of the mobile axis body. The permanent magnet is magnetized in the axial direction of the mobile axis body and disposed between the first yoke and the second yoke.

Abstract: A method for actively suspending a real plant in a vehicle includes modifying a control signal on the basis of a difference between a property of the real plant, as indicated by the response of the real plant to the control signal, and a property of a nominal plant.

Abstract: An anti-vibration support system for an engine, comprising an active anti-vibration supporting device including an elastic member adapted to receive a vibration of the engine; a liquid chamber, wherein at least a portion of a wall surface of said liquid chamber is defined by said elastic member; a movable member adapted to change a volume of said liquid chamber; and an actuator that uses an electromagnetic force to drive said movable member, wherein the vibration of the engine is prevented from being transmitted to a vehicle body frame by controlling a supply of electric current to said actuator, and wherein operation of said active anti-vibration supporting device is prohibited when an abnormality in an operational state of the engine is detected.

Abstract: In an active fluid-filled engine mount, a oscillation member is excited and displaced by an electromagnetic actuator, and thereby pressure in a pressure receiving chamber is actively controlled. A short circuit passage is provided connecting the pressure receiving chamber and an equilibrium chamber. A ratio of a passage cross-sectional area and a passage length of the short circuit passage (a/l) is provided greater than a ratio of a passage cross-sectional area and a passage length of the first orifice passage (A/L) (A/L<a/l). The passage cross-sectional area of the short circuit passage (a) is provided smaller than the passage cross-sectional area of the first orifice passage (A) (a<A).

Abstract: The invention relates to a method for damping vibrations on chassis bearings of motor vehicles, and a device for implementing the process. A process and a device are to be presented with which outstanding vibration damping and vibration isolation and noise insulation can be achieved over a wide frequency range with consideration of the driving states and roadway conditions which occur in motor vehicles. For this purpose it is proposed that the driving state of the motor vehicle and/or the roadway conditions are detected by way of sensors and that the at least one chassis bearing is modified to different characteristics to change its stiffness and/or damping depending on the detected parameters.

Abstract: A method of designing a magnetorheological (MR) fluid energy absorbing damper is provided that uses hydromechanical analysis with lumped parameters to allow a determination as to whether a potential damper design will provide predetermined characteristics, such as a desired dynamic force range and maximum piston velocity, with a selected MR fluid and yield stress and preferably meeting predetermined geometric limitations.

Abstract: An active vibration isolation support system includes an electronic control unit which supplies a target electric current to an actuator to periodically drive the actuator in an expansion and contraction manner with a target vibration waveform. The controller sets the target electric current by synthesizing a driving primary electric current waveform corresponding to the target vibration waveform for the actuator with higher-order (driving secondary and/or tertiary) electric current waveforms which eliminate higher-order vibration components of the actuator corresponding to the driving primary electric current waveform. It is possible to alleviate a calculating load in the electronic control unit by ignoring the quaternary and still higher-order vibration components which less affect the target vibration waveform for the actuator.

Abstract: An object of the present invention is to obtain a vibration damper capable of instantly changing or rapidly increasing the spring constant of the vibration damper, with improving sealing properties. An intermediate cylinder 16 is fittingly engaged with the inner peripheral surface of an outer cylindrical metal member 12. The intermediate cylinder 16 and a mounting metal member 22 are elastically connected by a rubber elastic body 24. A circular tube portion 36A of a yoke forming member 36 is provided at a position on the inner peripheral side of the intermediate cylinder 16. A coil 46 is to disposed between the intermediate cylinder 16 and the yoke forming member 36.

Abstract: An active vibration damper including: an inner shaft member provided to a movable member; an outer tube member provided to a stator; a pair of leaf springs elastically connecting axially both sides of the inner shaft member and the outer tube member so as to make a linear actuator operatable by itself; an elastic connecting rubber connecting the inner shaft member and the outer tube member; a mass body holding portion provided to the inner shaft member for holding an additional mass body that is disposed further outwardly than the elastic connecting rubber; and a housing having a structure dividable in an axial direction in which respective openings are secured to each other with an annular seal being interposed therebetween at an outer peripheral side of the elastic connecting rubber.

Abstract: A fluid-filled vibration damping device wherein a partition member is formed by fitting an inner orifice member inside an outer orifice member with the members relatively displaceable. An orifice-defining window is provided on either one of an inside peripheral face of the outer orifice member and an outside peripheral face of the inner orifice member. An orifice passage is defined utilizing a zone being produced through partial covering of the orifice-defining window by the other of the outer orifice member and the inner orifice member. The covered zone of the orifice-defining window changes through relative displacement of the inner orifice member and the outer orifice member, so that a passage length along the orifice passage changes in association with change of the covered zone of the orifice-defining window.

Abstract: A fluid-filled type vibration damping device having a first and a second fluid chamber respectively filled with non-compressible fluid and which experience relative pressure fluctuations during vibration input, and provided with an orifice passage through which the first fluid chamber and the second fluid chamber communicate with one another, while being capable of exhibiting better dependability and durability in terms of effective vibration damping action of several types of vibration with different frequencies. In the device, tuning frequency of the orifice passage is varied by varying a passage length of the orifice passage 68 through adjustment of an insertion distance of an inside orifice member into an outside orifice member.

Abstract: According to one embodiment, a vibration isolation system includes a heater element thermally coupled to a damping element formed of an elastomeric material having an elasticity that varies as a function of its temperature. The damping element physically couples a first structure to a second structure. The heater element selectively heats the damping element to regulate its temperature for controlling the elasticity of the damping element.

Abstract: In order to control vibrations of two parts of a piece of machinery, a variable force may be generated to oppose the vibrations, with the variable force being generated under control of a controller on the basis of an iterative relationship, the iterative relationship being such as to generate the force of one iteration using a controller output signal in frequency domain vector form derived from the controller output signal of the immediately previous iteration in frequency domain vector form plus a frequency domain vector quantity derived from the resultant vibration of more than one previous iteration. Where these two parts are connected by multiple (f) mounting devices, the controller output signals a previous iterations are taken into account, and the frequency domain vector quantity derived from the controller output signals and more than f previous iterations.

Abstract: A fluid-filled type active vibration damping device including a vibration damping device main unit, an oscillation member, and an actuator. The actuator is constituted by an electromagnetic actuator having a stator that includes a coil fixed to a second mounting member while having a movable member linearly displaceable relative to the stator when the coil is energized. A shaft member is provided for connecting the movable member and the oscillation member with each other. A connecting portion is provided for attaching the shaft member to the movable member while permitting the shaft member to tilt as well as to undergo displacement in an axis-perpendicular direction with respect to the movable member. A displacement preventing portion is provided for fastening the movable member and the shaft member to each other by preventing tilt as well as displacement in the axis-perpendicular direction due to the connecting portion.

Abstract: A conically-shaped, magneto-rheologically responsive shock and vibratory isolator. The isolator includes a conically-shaped magneto-rheological elastomer component attached to opposing faces of a first and second mounting plate. Within the magneto-rheological elastomer component is a magneto-rheologically responsive fluid contained within an elastomer jacket. By its conical shape and magneto-rheological elastomeric composition, the isolator is capable of both adjusting its response to shock and vibratory disturbances of varying frequency, while maintaining an identical response along any axis (isoelasticity).

Abstract: A vibration isolation system isolates a body from its surroundings with respect to vibrations. The vibration isolation system includes active isolator devices that isolate and damp the body in unstable directions. However, such active isolators may exert damping forces not only in the unstable direction, but simultaneously in other stable directions due to mechanical coupling of the stable and unstable directions. As a result the damping and isolation in the other stable directions may be deteriorated due to the active isolation and damping. Employing modal decoupling, i.e. decomposing any vibration into independent directions, and isolating and damping in the independent directions, enables compensation of any vibration in an unstable direction without influencing the isolation and damping performance in any other, possibly stable, direction.

Abstract: An electromagnetic actuator having: a stator and a movable member disposed in a central hole of a coil member of the stator movable in an axial direction; a coupling rod fixed to the movable member; and an elastic stopper having a ring shaped sealing unit at its outer periphery part, a first stopper unit at its center part, a coupling unit that mutually couples the sealing unit and the first stopper unit, and second stopper units located radially between the sealing unit and the first stopper unit at respective circumferential positions. The sealing unit is compressed between the bottom wall of a housing and a lid member to form a sealing mechanism that fluid-tightly close an opening of an adjustment hole. The first stopper unit axially faces the coupling rod bottom with a first separation distance, and the second stopper units axially face the movable member bottom with a second separation distance greater than the first.

Abstract: In a so-called motoring state at the time of engine starting before actuating engine, there is a problem that a roll vibration, which is generated when an engine revolution speed Ne is at a predetermined engine revolution speed and vibrates the engine and the vehicle body largely, can not be suppressed. For this reason, the present invention provides an active vibration isolating support apparatus in which the roll vibration can be suppressed in the motoring state at the time of engine starting.

Abstract: A vehicle suspension system including: (a) a suspension spring interconnecting a vehicle body and a wheel; (b) an actuator having an electric motor, such that the actuator is capable of generating, based on a force of the electric motor, an actuator force forcing the body and the wheel toward and away from each other, and causing the generated actuator force to act as a damping force against displacement of the body and the wheel; and (c) a control device for controlling the actuator force generated by the actuator, by controlling operation of the electric motor. The control device is capable of establishing a constant-force generating state in which the actuator force is constantly generated as a constant actuator force by the actuator with supply of an electric power thereto from a battery as an electric power source of the electric motor such that the generated constant actuator force acts in a rebound direction or a bound direction.

Abstract: The invention relates to a device for mounting an anti-vibration actuator on an automobile. The device comprises a fastening screw for attaching the actuator on a wall of a frame of the vehicle. The main characteristic of the mounting device is that it comprises a slide attached to the vehicle frame wall, and that the actuator comprises a protrusion capable of being inserted into the slide (19, 29, 39) so that the actuator has two connection points to the wall.

Abstract: An automobile vibration damping device for an automobile in which a power plant in which an engine, a transmission and the like are combined is supported by a vehicle body, including a vibrating means that generates vibration separate from vibration of the engine. Thereby, it is possible to reduce the vibration amplitude of a seat portion by the reaction force of the vibrating means. Also, if the vibration mode of the vehicle body is adjusted so as to become a node in the vicinity of the seat portion, the vibration amplitude decreases in the vicinity of the seat portion, and improves riding comfort.

Abstract: An object of the present invention is to provide an active vibration isolating support apparatus to effectively reduce a transient vibration which occurs at the time of engine starting. In order to achieve the above object, an active vibration isolating support apparatus for suppressing a vibration transmitted to a vehicle body including: active mounts to elastically support a load of an engine in the vehicle body each of which includes an actuator; and a control unit to drive the actuator to extend and contract periodically in response to a waveform of the vibration of the engine; in which the control unit supplies a predetermined current to the actuator based on a starting control condition, and starts a control of the actuator based on a control instruction value of a current in response to the vibration of the engine is provided.

Abstract: In a V6 engine that can switch between a first running state and a second running state which differ in the number of cylinders that are permitted to operate, when switching from L3 selective cylinder operation to V4 selective cylinder operation is determined to be required, control of an active vibration isolation support system corresponding to L3 selective cylinder operation is normally continued for one cycle. However, in this case of switching from L3 selective cylinder operation to V4 selective cylinder operation, a vibration pattern of L3 selective cylinder operation continues for longer than usual, that is, for a period greater than one cycle. Therefore, control of the active vibration isolation support system corresponding to the vibration pattern of L3 selective cylinder operation is continued for two cycles of the vibration pattern, thereby further effectively improve a vibrational state when switching between running states from L3 selective cylinder operation to V4 selective cylinder operation.

Abstract: A suspension device S interposed between a sprung member B and an unsprung member W of a vehicle, comprising an actuator A, a hydraulic damper D, and a direction changing mechanism T for changing a linear motion of the actuator A into a linear motion in an opposite direction and transmitting the opposite linear motion to the hydraulic damper D. When a high-frequency vibration acts on the unsprung member, the drawback that the vibration is apt to be transmitted to the sprung member B under the influence of moment of inertia of the actuator A is remedied and it is possible to improve the ride comfort in the vehicle.

Abstract: An hydraulic mount providing double idle rate dip frequencies of dynamic stiffness, the idle rate dips being vibration orders of an internal combustion engine corresponding to one and two times firing frequencies. The double idle rate dip is achieved by providing the first idle rate dip at the first vibration order via resonance tuning of the idle inertia track, and providing the second idle rate dip at the second vibration order via additional resonance tuning of a tunable air conduit.

Abstract: A hydraulically damping elastomer bearing has at least one housing (1, 2), a connection element (3), an elastomer body (4), which couples the housing (1, 2) and the connection element (3) with one another in a vibration-damping manner. Two chambers (5, 6) filled with a fluid are provided as well as at least one flow channel (8), which connects the chambers (5, 6) to one another. A recess (9) in the housing (1, 2) is associated with the flow channel (8). A valve (10) is present in the recess (9) for opening and closing the flow channel (8). An actuator (11) is provided for actuating the valve (10) on the outside of the housing (1, 2). The valve (10) includes an elastic diaphragm (12), in which an insert (13) is embedded.

Abstract: In an electromagnetic actuator including a bearing member which slidably supports a variable core, a yoke for retaining a coil assembly by cooperation with a bottom wall of a housing is connected to the housing, and the bearing member is fitted into the yoke. A support for supporting an outward-facing flange formed at one end of the bearing member is mounted on the bottom wall, and a set spring for biasing the outward-facing flange toward the support is mounted under compression between the outward-facing flange and the first yoke. A low-friction material coating made of a fluorocarbon resin is formed on at least one of opposed sliding surfaces of the bearing member and a movable core. Thus, even if wear powder is generated between the set spring of the bearing member and a portion on which the set spring is pressed, the wear powder is prevented from entering inside the bearing member.

Abstract: Devices and methods are provided to facilitate measurement of forces acting on locations connecting a subframe portion and a body portion of a vehicle, such devices and methods include mount devices having an inner member, an outer member, at least one sensor, a sleeve and an annular member. The sensor is disposed within an annular chamber formed between the inner member and the outer member. The sensor is attached to at least one of the inner member and the outer member. The sensor is configured to measure force exerted on the mount device during use of a vehicle. Vehicles including these mount devices are also provided.

Abstract: A vibrational energy absorbing apparatus 1 includes: a reciprocating member 2 which is reciprocatable in H directions between positive and negative maximum displacement positions D±max with respect to an origin position O; a damping-force generating means 3 for generating a damping force R with respect to the reciprocating motion of the reciprocating member 2 in the H directions; and a controlling means 4 for controlling the damping-force generating means 3 so as to cause the damping-force generating means 3 to generate a fixed damping force R in the respective movement of the reciprocating member 2 in the H direction from the positive and negative maximum displacement position D±max to the origin position O in the reciprocating motion thereof in the H directions, while causing the damping-force generating means 3 to substantially not generate the damping force R in the respective movement of the reciprocating member 2 in the H direction from the origin position O to the positive and negative maximum displace

Abstract: An electromagnetic active engine mount apparatus includes a sub-channel through which working fluid flows is formed in the central portion of an electromagnetic drive so as to be able to cool heat generated from the coil of a solenoid section of the electromagnetic drive by repetitive operation of a vibrating member. Thus, the electromagnetic active engine mount apparatus can inhibit the heat generated from the coil to thus prevent thermal damage to various components formed of rubber, and provide improvement of its durability, reduction of its size, and simplification of its structure.

Abstract: Particular embodiments relate generally to vibration isolation systems and tuned mass dampers. In one embodiment, a vibration isolation system may include a supporting base, an isolated mass, at least one air mount, a control valve, a compressed air supply, and a supervisory controller. The air mount is positioned between the isolated mass and the supporting base. The control valve is pneumatically coupled to the air mount, the compressed air supply and the atmosphere, and is operable to adjust a flow of air to and from the air mount. The supervisory controller receives a mass relative height signal, a mass relative velocity signal, and a mass relative acceleration feedback signal corresponding to a relative acceleration of the isolated mass or a pressure of the air mount.

Abstract: A first expression of an embodiment of the invention is for apparatus including a magnetorheological-fluid (MR-fluid) hydraulic mount. The mount includes an internal MR-fluid cavity and a partition plate assembly. The partition plate assembly partitions the cavity into first and second MR-fluid chambers. The mount is adapted to receive an MR-fluid pressure sensor in fluid communication with the second MR-fluid chamber. A second expression of an embodiment of the invention is for apparatus including an MR-fluid hydraulic mount. The mount includes an internal MR-fluid cavity, a partition plate assembly, and an MR-fluid pressure sensor. The partition plate assembly partitions the cavity into first and second MR-fluid chambers. The MR-fluid pressure sensor is in fluid communication with the second MR-fluid chamber.

Abstract: An electromagnetic active engine mount includes a main body having a chamber in which non-compressive fluid is encapsulated, and an anti-vibration rubber installed at an upper portion thereof, and an electromagnetic driver having a vibrating unit for generating vibration when vibration is transmitted from an engine, and a solenoid installed at a lower portion of the vibrating unit in order to control the vibration of the vibrating unit.

Abstract: A magnetorheological damper system comprising a reservoir in communication with a damper. The damper comprises a damper cylinder defining a damper chamber, wherein the damper chamber contains a magnetorheological fluid and a movable damper piston. The damper piston comprises at least two coil windings on the outer surface of the damper piston, wherein the damper piston is capable of generating a magnetic field between the damper piston and a wall of the damper cylinder. The reservoir comprises a reservoir cylinder defining a passageway, wherein the reservoir includes a magnetorheological electromagnet capable of generating a magnetic field between the magnetorheological piston and a wall of the passageway. The combination of the an MR reservoir and MR damper leads to a damping system capable of damping a wide range of extreme forces.

Abstract: An object of the present invention is to provide an active vibration isolating support apparatus to effectively reduce a transient vibration which occurs at the time of engine starting. In order to achieve the above object, an active vibration isolating support apparatus for suppressing a vibration transmitted to a vehicle body including: active mounts to elastically support a load of an engine in the vehicle body each of which includes an actuator; and a control unit to drive the actuator to extend and contract periodically in response to a waveform of the vibration of the engine; in which the control unit supplies a predetermined current to the actuator based on a starting control condition, and starts a control of the actuator based on a control instruction value of a current in response to the vibration of the engine is provided.

Abstract: When switching between L3 cylinder cut-off running in which a bank on one side of a V6 engine is cut off and V4 cylinder cut-off running in which one cylinder in each of the two banks is cut off, V6 all-cylinder running to operate all the cylinders is interposed therebetween. Therefore, a transitional period is provided between L3 cylinder cut-off running and V6 all-cylinder running and between V6 all-cylinder running and V4 cylinder cut-off running, and no transitional period is present between L3 cylinder cut-off running and V4 cylinder cut-off running. Thus, it is possible to simplify control of an active vibration isolation support system during the transitional period and to avoid deterioration of a vibrational state during the transitional period.

Abstract: What is described is an oscillation decoupling device with a load-receiving element which is mounted in an oscillating manner relative to a support unit at least along an active direction along which at least part of the load is applied, and with at least one sensor-actuator unit which detects an oscillation of the element due to the load and acts against the oscillation of the element by means of actuators. The invention is characterised in that the support unit is modularly configured and serves as a support structure for at least one unit that receives the element and is elastically deformable in the active direction of the load, in that the load-receiving element is connected to the elastically deformable unit, and in that an actuator influencing the deformation is applied to the at least one unit, or is integrated in it, so that the actuator initiates a deformation acting against an elastic deformation due to the load inside the unit.

Abstract: When driving an actuator 41 of an active vibration isolating support apparatus M to extend and contract on a predetermined cycle so as to suppress the transmission of vibrations of an engine, since a combined target current ICMDT is calculated by combining a primary target current which cancels a primary vibration of the engine with a secondary target current which cancels a secondary vibration of the engine and furthermore, the actuator 41 is driven with a target driving current ICMD in which a minimum value of the combined target current ICMDT is offset to 0, can the primary vibration and the secondary vibration of the engine be cancelled so as to enhance a vibration isolating function and the inclusion of a direct current component into the target driving current ICMD can be prevented so as to suppress a wasteful heat release of the actuator 41 to a minimum level.

Abstract: A sealing member which seals a sealed space where a movable core of an electromagnetic actuator is arranged, includes: an inner ring portion and an outer ring portion which are respectively arranged inside and outside in the radial direction, come into contact with the upper surface of a flange of a fixed core and the lower surface of a coil assembly, and are compressed therebetween; and a thin connection portion integrally connecting the inner and outer ring portions. Therefore, the inner and outer ring portions are compressed and escape toward the upper and lower surfaces of the thin connection portion, whereby the axial thickness of the sealing member can be reduced in an assembled state while securing the sealability of the sealing member.

Abstract: An active vibration damping device wherein first and second mounting members are linked by a main rubber elastic body, a pressure receiving chamber having a non-compressible fluid sealed therein is defined by the main rubber elastic body at one part and by an oscillation member in the other part. A solenoid actuator designed with a movable element positioned inserted into a guide hole of a stator having a yoke member is attached about a coil to form a stator-side magnetic path with the guide hole lying on its center axis, so that current passed through the coil creates actuating force in the axial direction between the stator and the movable element. The stator of the solenoid actuator is affixed to the second mounting portion and the movable element is attached to the oscillation member. A bias urging assembly is disposed for urging the movable element in one axis-perpendicular direction to the stator.

Abstract: An electromagnetic shock absorber including: (a) a wheel-side member; (b) a body-side member movable relative to the wheel-side member; and (c) a damping force generator with an electromagnetic motor including stationary and movable elements movable relative to each other. The damping force generator can generate, based on a force generated by the motor, a damping force acting against a relative movement of the wheel-side member and the body-side member. The motor has an axis extending in a both-members-relative-movement direction as a direction of the above-described relative movement. The stationary element is supported by the wheel-side member via an elastic body, to be movable relative to the wheel-side member in the both-members-relative-movement direction. The electromagnetic motor allows relative movement of the stationary element and the movable element upon movement of the stationary element relative to the wheel-side member.

Abstract: A fluid filled vibration damping device including: a fluid passage interconnecting a pressure receiving chamber partially defined by a rubber elastic body connecting a first and second mounting members, and an equilibrium chamber partially defined by a flexible film; a movable valve body provided for switching the fluid passage between a communicating state and a blocked state through reciprocating operation; an electric motor employed for actuating the movable valve body; an actuating force converter mechanism provided on an actuating force transmission path from the electric motor to the movable valve body. A rotational actuating force of the electric motor is transmitted as reciprocating actuating force to the movable valve body by the actuating force converter mechanism.

Abstract: An engine mount system includes multiple liquid-filled engine mounts switchable to provide different mount characteristics by selectively introducing negative pressure or atmospheric pressure. On one of pipelines connected to the respective engine mounts for introducing the negative or atmospheric pressure into the respective engine mounts, a check valve and an orifice portion are provided in parallel. The orifice portion restricts an amount of air flowing therethrough, so that the mount characteristic of the engine mount connected to the one pipeline equipped with the check valve and the orifice portion does not undergo an abrupt change when the pressure introduced in the engine mount is switched from the negative pressure to the atmospheric pressure.

Abstract: Microelectromechanical systems (MEMS) include critical devices for various highly sensitive applications. However, MEMS operation may be impaired by vibration. A modular vibration control pedestal for integration with a MEMS is provided according to embodiments of the present invention which includes a piezoelectric perovskite oxide disposed on a substrate and a shape memory alloy component disposed on the piezoelectric perovskite oxide. In particular embodiments of a MEMS device including a modular VCP, vibration is reduced by at least 50%.

Abstract: An antivibration device for supporting loads and damping vibration between external elements. The antivibration device comprises two rigid members and a resilient body for supporting loads and partially damping vibrations The antivibration device also comprises a damping unit for further damping of vibrations coincidentally with the resilient body.

Abstract: It is an object of the invention to improve the utility of an electromagnetic absorber system which is disposed in a suspension system of a vehicle and which generates a damping force by a generation force of a motor. The electromagnetic absorber system 18 is equipped with high-speed-motion responding means, thereby obviating an insufficiency of the damping force and a deterioration of the controllability in a high-speed stroke motion. More specifically, a hydraulic absorber 64 is provided in combination with the electromagnetic absorber system such that the hydraulic absorber 64 operates in the high-speed motion in which an electromotive force of the motor 68 exceeds a power source voltage Further, two motors having mutually different T-N characteristics are provided, and the two motors are selectively operated depending upon a stroke speed.

Abstract: A vibration damping device including: a rubber elastic body connecting first and second mounting members; a partition member supported on the second mounting member; a pressure-receiving chamber and an equilibrium chamber connected by a first orifice passage; an oscillating plate defining the pressure-receiving chamber; and an electromagnetic actuator for actuating the oscillating plate. The oscillating plate is constituted by a cylinder shaped hole and a piston shaped plate accommodated within the cylinder shaped hole with a gap provided therebetween. An output member of the electromagnetic actuator is linked to the piston shaped plate. A plate spring extending in an axis-perpendicular direction is disposed to an opposite side from the electromagnetic actuator with the piston shaped plate therebetween, with the oscillating plate linked to and supported in an axial direction with respect to the partition member by the plate spring.

Abstract: A vibration damping device including: a pressure-receiving chamber and an equilibrium chamber connected by a first orifice passage; a movable member disposed within the pressure-receiving chamber, to form a primary fluid chamber partly defined by a rubber elastic body, and an auxiliary fluid chamber partly defined by an oscillating plate; and a second orifice passage connecting the auxiliary fluid chamber to the equilibrium chamber. A through-hole is formed in a partition member that partitions the primary fluid chamber and the auxiliary fluid chamber, the oscillating plate is housed within the through-hole with a gap provided therebetween whereby the oscillating plate is displaceable in an axial direction within the through-hole. A stopper abutted by the oscillating plate during displacement to one axial side is provided, with the gap becoming closed off when the oscillating plate is in a state of abutment against the stopper.

Abstract: An electromagnetic actuator includes a fixed core supported by a bottom wall of a housing, a movable core arranged opposite to the fixed core via an air gap to drive the movable member, and coil assembly supported by the housing to surround both the cores, wherein the movable member and the movable core are connected by connecting means for adjusting the air gap between the fixed core and the movable core, and wherein an adjustment operating hole through which the connecting means is adjusted is provided on the fixed core so as to be opened outside the bottom wall of the housing. Thus, it is possible to freely adjust the air gap between the fixed core and the movable core without preparing several types of connecting members.