Abstract: An active vibration damper including: an electric-type linear actuator having a stator, a movable member; a coil arranged in one of the stator and the movable member; a mounting member to which the stator is fixed; a mass member incorporating the movable member; an elastic connecting rubber connecting the mass member to the stator, and being disposed such that the linear actuator is disposed on one side thereof so that the mass member is oscillated by means of driving force applied to the movable member of the linear actuator; a cover member firmly fixed to the mounting member for providing a hermetic accommodation space having a first air chamber and a second air chamber formed on both sides of the elastic connecting rubber; and an air channel through which the first and the second air chambers are communicated.

Abstract: An adaptive controller includes an adaptive-signal generator for generating an adaptive signal, which includes a first amplitude filter coefficient and a first phase filter coefficient, in a first transfer path based on an angular frequency of a cyclic signal, which a vibration generation source generates; a first residual-error detector for detecting a first residual error at a first observation point in the first transfer path; an observation-point target-value setter for setting a residual-error target value, which includes an amplitude target value complying with the angular frequency; and a first filter-coefficient updater for updating the first amplitude filter coefficient and the first phase filter coefficient based on the angular frequency, the first residual error and the residual-error target value. Thus, when adding the adaptive signal to the cyclic signal, the adaptive controller can make the residual error, which results from the addition, not equal to zero intentionally.

Abstract: A fluid-filled type vibration-damping device having a movable rubber plate housed within a partition member partitioning a pressure-receiving chamber and an equilibrium chamber from each other. The movable rubber plate is moved owing to the pressure difference between the two chambers. The movable rubber plate comprises the movable rubber plate formed of a generally disk shaped rubber elastic body having formed thereon in alternating fashion concave grooves and convex ribs each extending in a circumferential direction about a same center axis, the convex ribs have tapered cross section gradually narrowing in width towards an distal end thereof, and the concave grooves and convex ribs are disposed at the same locations in a diametrical direction on either face of the movable rubber plate so that the thickness of the movable rubber plate is varied in the circumferential direction.

Abstract: A fluid-filled type vibration-damping device having an elastic rubber film partially defining a primary fluid chamber at one surface and partially defining a pressure action chamber. The pressure action chamber varies its pressure under control so that the elastic rubber film changes its elasticity to change damping characteristics of the device. To give sufficient recovery force for the elastic rubber film, the elastic rubber film includes a plurality of thick reinforcing ribs circumferentially spaced apart from one another and extending in a radial direction from an outside peripheral edge over a length not reaching a center so that areas situated between pairs of adjacent reinforcing ribs constitutes thin portions formed by a thin rubber elastic body, while the center portion of the elastic rubber film situated between distal ends constitutes a bowed center portion thinner than the reinforcing ribs and convex towards the pressure action chamber.

Abstract: A fluid-filled type vibration damping device including: a primary fluid chamber partially constituted by a main rubber elastic body connecting a first and second mounting member; an equilibrium chamber partially constituted by a flexible film; a partition member supported by the second mounting member; and a partition rubber film is superimposed against the partition member and secured interlocking with an annular interlocking projection projecting from the partition member. A first seal rubber is compressed between the interlocking projection and the tubular fitting member and extending about the entire circumference, thereby forming a working air chamber therebetween. A gap is furnished between and a second seal rubber is compressed between the tubular fitting member and the orifice member, and extending about the entire circumference.