Abstract: A vibration-damping device includes: a damper mass having a housing member with an accommodation space, an independent mass member housed within the accommodation space with a slight spacing therebetween so that the independent mass member is independent of the housing member and is freely displaceable within the accommodation space of the housing member to come into impact on the housing member via an elastic member; and a metallic spring member to be fixed at a plurality of fixing portions thereof on the vibrative member for elastically supporting the damping mass vibrative member, such that the housing member of the damper mass is fixed to a portion of the metallic spring member through which a principal elastic axis of the metallic spring member extends, and that a center of gravity of the damper mass is located on the principal elastic axis of the metallic spring member.

Abstract: A fluid-filled vibration damping device including: an elastic body connecting a first and a second mounting member, defining a pressure receiving chamber undergoing pressure fluctuation during input of vibration; an equilibrium chamber defined by a flexible layer for permitting its volume change; an orifice passage connecting the pressure receiving chamber and equilibrium chamber; a movable member; and a short passage for connecting two chambers with a length smaller than that of the orifice passage. When pressure in the pressure-receiving chamber increases, the movable member is displaced or deformed toward to close the equilibrium-chamber-side opening of the short passage to have the short passage substantially closed, while when pressure in the pressure-receiving chamber decreases, the movable member is displaced or deformed to have the short passage operative.

Abstract: A fluid-filled vibration damping device including: an elastic body connecting a first and a second mounting member, defining a pressure receiving chamber undergoing pressure fluctuation during input of vibration; an equilibrium chamber defined by a flexible layer for permitting its volume change; a first orifice passage connecting the pressure receiving chamber and equilibrium chamber; a medial chamber disposed between the pressure receiving chamber and equilibrium chamber; a second orifice connecting the pressure receiving and medial chambers, being tuned to a frequency higher than does the first orifice passage; a pressure fluctuation transmitting mechanism disposed between the pressure receiving and medial chambers for a restricted pressure transmission between chambers by restrictive displacement of its movable member; and a pressure regulating rubber plate defining the medial chamber, regulating pressure fluctuation in the medial chamber by its elastic deformation.

Abstract: A series-type engine mount provided in a selectively combined arrangement (B-1), (B-2) or (B-3), with an mount body (A). (A) A fluid-filled mount body has an elastic body connecting a first and second mounting member; a pressure receiving chamber defined by the elastic body; an equilibrium chamber defined by a flexible layer; a first orifice passage connection the pressure receiving and equilibrium chambers; a medial chamber; a second orifice passage connecting the medial and equilibrium chambers; a pressure fluctuation transmitting mechanism; a pressure regulating rubber plate; an air chamber; and an air passage connected to the air chamber with a port. (B-1) The port is open to an atmosphere to expose the air chamber to atmosphere. (B-2) The port is connected alternatively to atmosphere and vacuum via a static pressure switching valve. (B-3) The port is cyclically switched between connection to atmosphere and vacuum via a dynamic pressure switching valve.

Abstract: A fluid filled vibration damping device includes an elastic body connecting a first and a second mounting member to close one opening of the second mounting member, and a lid member is fixed caulkwise to a shoulder of the second mounting member to close the other opening of the second mounting member, thereby providing a fluid chamber filled with a noncomporessible fluid. A partition member of outside diameter smaller than the inside diameter of the cylindrical caulking portion is formed with engaging projections rising up with a uplift cutout form. The engaging projections is fit into the second mounting member with the partition member superimposed on the shoulder so that the second mounting member is positioned in an axis-perpendicular direction to the second mounting member. Cutout openings left after the engaging projections have been formed are closed by a sealing portion.

Abstract: A vibration-damping device for damping vibrations of a vibrative member, which includes a damper mass member having a rigid abutting portion, a spring member for elastically connecting the damper mass member to the vibrative member to cooperate with the damper mass member to constitute a second vibration system whose natural frequency is tuned to a frequency band of the vibrations of the vibrative member, and an independent mass member disposed so as to be opposed to the rigid abutting portion in a vibration input direction with a given gap therebetween without being adhesive to the rigid abutting portion. The independent mass member is independently displaceable relative to and brought into abutting contact directly and elastically with said rigid abutting portion in said vibration input direction.

Abstract: A fluid filled vibration-damping device includes an elastic body disposed between a first mounting member and a second mounting member and partially defines a fluid chamber having a non-compressible fluid sealed therein, and exhibits vibration damping action on the basis of flow action of the non-compressible fluid created within the fluid chamber during vibration input. At least one mounting member from among the first and second mounting members is formed independently of the elastic body and is disposed in abutment with the elastic body in an initial load acting direction, while making the mounting member displaceable away from the rubber elastic body in a opposite direction from the initial load acting direction. A rebound stop mechanism for limiting displacement of the mounting member away from the rubber elastic body in a cushion-wise fashion is disposed between the first and second mounting members.

Abstract: A vibration damping device having a stopper structure includes: a rubber elastic body of generally frustoconical configuration overall; a first mounting member formed independently of the rubber elastic body, and directly or indirectly superimposed on the rubber elastic body in an external load input direction; and a second mounting member including a cylindrical portion that is bonded to a large diameter side outer circumferential surface of the rubber elastic body. A first and second abutting portions of the first and second mounting members are situated to be opposed to each other in a rebound direction with a given distance interposed therebetween, and a stop rubber is disposed between the first and second abutting portions so that the first and second abutting portions come into abutting contact with each other in a cushion-wise fashion, via the stop rubber to thereby provide a stopper structure.

Abstract: A vibration damping actuator including: a guide hole open onto a bottom face of a housing; a lid metal plate fitted into the opening of the guide hole with a size enough to hinder inward displacement thereof into the guide hole by an annular shoulder portion; an engaging groove disposed on an inner circumferential surface of the opening; a snap ring of C-letter shape fitted into the engaging groove to prevent the lid metal plate from becoming dislodged from the opening; and a sealing rubber layer formed covering an inside face of the lid metal plate. The lid metal plate is pressed by the snap so that the sealing rubber layer is pushed against the annular shoulder portion, thereby sealing the opening of the guide hole.

Abstract: A vibration damping actuator including: a cup-shaped housing; an output member disposed spaced apart from an opening end of the housing; a guide rod disposed on the output member and positioned inserted into a guide hole; a coil member provided to one of the housing and the output member; an armature disposed on an other of the housing and the output member, the armature being adapted to exert actuating force on the output member; an annular fixing member arranged about the output member; a support rubber plate disposed between the annular fixing member and the output member; and a positioning projection formed at an inside peripheral edge of the fixing member by projecting the inside peripheral edge of the fixing member in cylindrical configuration in an axial direction towards an inside of the housing. The positioning projection is disposed at a location situated inward by a predetermined distance from the opening of the housing for positioning the fixing member relative to the housing.

Abstract: A fluid filled vibration damping device includes an elastic body connecting a first and a second mounting member to close one opening of the second mounting member, and a lid member is fixed caulkwise to a shoulder of the second mounting member to close the other opening of the second mounting member, thereby providing a fluid chamber filled with a noncomporessible fluid. A partition member of outside diameter smaller than the inside diameter of the cylindrical caulking portion is formed with engaging projections rising up with a uplift cutout form. The engaging projections is fit into the second mounting member with the partition member superimposed on the shoulder so that the second mounting member is positioned in an axis-perpendicular direction to the second mounting member. Cutout openings left after the engaging projections have been formed are closed by a sealing portion.

Abstract: A fluid filled vibration damping device including: an elastic body elastically connecting a first and a second mounting member and partially defining a pressure receiving chamber filled with a non-compressible fluid and undergoing fluid pressure variation upon application of vibrational load between the first and second mounting members; a flexible diaphragm partially defining an equilibrium chamber filled with the non-compressible fluid and whose volume is variable; and an orifice passage permitting a fluid communication between the pressure-receiving chamber and the equilibrium chamber. The flexible diaphragm is constituted by a rubber elastic layer having an annular thick-walled portion and a central thick-walled portion situated at a substantially central portion of an inner area surrounded by the annular thick-walled portion, while being independent of the annular thick-walled portion.

Abstract: A fluid filled vibration damping device including: an elastic body elastically connecting a first and a second mounting member and partially defining a pressure receiving chamber filled with a non-compressible fluid; a flexible diaphragm partially defining an equilibrium chamber filled with the non-compressible fluid and connected to the pressure-receiving chamber via an orifice passage. The first mounting member includes an elastic-body-side central member bonded to the elastic body central portion, and a rubber-layer-side central member bonded to the flexible rubber layer central portion, both mutually superposed on and fastened together by a connecting bolt. A fitting recess and projection are formed at an interface between two members, and a mounting projection projecting outward on an opposite side from the interface. The connecting bolt is off-centered from a center of the two members by a give distance.

Abstract: A damping performance evaluation apparatus for damping devices including: a support member detachably supporting a damping device in a state enabling the device to exhibit a damping effect thereof; a hammer member for applying oscillation force to the device caused by gravitational descent to strike the device; a double-strike preventing member for preventing the hammer member from dropping a second time due to rebound after initially striking the device, to prevent double-strike of the device by the hammer member; a vibration sensor installed at a vibration zone caused to vibrate through oscillation force applied by said hammer member, for outputting an electrical signal in response to vibration at the vibration zone; and a sensing member for sensing a vibration mode in the vibration zone on the basis of an output of said vibration sensor. A damping performance evaluation method is also disclosed.

Abstract: A vibration-damping device includes a housing member and a pillar-shaped mass member housed within an accommodation space of the housing member with a slight spacing therebetween so that the mass member is freely displaceable within the accommodation space to come into impact on the housing member. A rubber buffer and an abutting rubber member integrally formed with each other and fixed to at least one of axial end portions of the mass member such that the rubber buffer covers an outer circumferential surface of the end portion of the mass member, and the abutting rubber member disposed over an end face of the axial end portion of the mass member. A void is formed between the abutting rubber member and the end portion of the mass member so that the abutting rubber member undergoes shear deformation upon an impact of the mass member on the housing member at the abutting rubber member.

Abstract: Disclosed is a damping performance evaluation apparatus for damping devices comprising: a support member detachably supporting a damping device in a state enabling the device to exhibit a damping effect thereof; a hammer member for applying oscillation force to the device caused by gravitational descent to strike the device; a double-strike preventing member for preventing the hammer member from dropping a second time due to rebound after initially striking the device, to prevent double-strike of the device by the hammer member; a vibration sensor installed at a vibration zone caused to vibrate through oscillation force applied by said hammer member, for outputting an electrical signal in response to vibration at the vibration zone; and a sensing member for sensing a vibration mode in the vibration zone on the basis of an output of said vibration sensor. A damping performance evaluation method is also disclosed.

Abstract: A vibration-damping device for damping vibrations of a vibrative member of a vehicle, including: a mass member disposed in the vibrative member such that the mass member is non-adhesive to and is displaceable independent of and relative to the vibrative member; the mass member and the vibrative member being brought into impact against with each other at their abutting portions. At least one of the abutting portions of the mass member and the vibrative member is formed of an elastic member adapted to undergo shear deformation in a direction in which the mass member and vibrative member are brought into impact against each other.

Abstract: A vibration-damping device includes: a damper mass having a housing member with an accommodation space, an independent mass member housed within the accommodation space with a slight spacing therebetween so that the independent mass member is independent of the housing member and is freely displaceable within the accommodation space of the housing member to come into impact on the housing member via an elastic member; and a metallic spring member to be fixed at a plurality of fixing portions thereof on the vibrative member for elastically supporting the damping mass vibrative member, such that the housing member of the damper mass is fixed to a portion of the metallic spring member through which an principal elastic axis of the metallic spring member extends, and that a center of gravity of the damper mass is located on the principal elastic axis of the metallic spring member.

Abstract: A vibration-damping device includes a housing member and a pillar-shaped mass member housed within an accommodation space of the housing member with a slight spacing therebetween so that the mass member is freely displaceable within the accommodation space to come into impact on the housing member. A rubber buffer and an abutting rubber member integrally formed with each other and fixed to at least one of axial end portions of the mass member such that the rubber buffer covers an outer circumferential surface of the end portion of the mass member, and the abutting rubber member disposed over an end face of the axial end portion of the mass member. A void is formed between the abutting rubber member and the end portion of the mass member so that the abutting rubber member undergoes shear deformation upon an impact of the mass member on the housing member at the abutting rubber member.

Abstract: A vibration restraining apparatus for vehicle of the present invention is comprised of a housing formed by a rigid material and having an inner space, and fixed to a vibration transmitting member; a filled member sealed in the inner space of said housing in a non-adhered state with leaving a gap with respect to a vibrating direction of said housing, and formed by an elastic body at least at a surface thereof. When the housing resonates by vibration transmitted from the vibration transmitting member, the filled member contacts inner surface parts located at both sides of the housing in a vibrating direction thereof to exercise a damping character due to an energy loss caused by a sliding friction and a collision. Thus, a large damping character occurs inside of the housing to reduce vibration of the housing effectively. As a result, vibration of the vibration transmitting member is effectively reduced.