Abstract: A dual-rate drive coupling (20) for use in transmitting drive torque between drive and driven members. The first torque rate is near zero for no-load and near no-load conditions. A pair of flexible elastomeric arms (24, 26) which is preferably bonded to the inner member (22) are received in recessed portions (44, 46) in the outer member (40) and provide the coupling with this first very low torque rate. When higher torque loading produces a relative rotation between the outer member (40) and the inner member (22) of at least about 15.degree., a pair of snubbing arms (28, 30) of the inner member (22) interact with surfaces of openings (48, 50) of the outer member (50). The contact surfaces of these second snubbing arms (28, 30) are coated with an elastomer to snub all contact between the inner member (22) and the outer member (40) to inhibit vibration induced rattling.

Abstract: An insert used to connect aircraft floor panels, and the like, to supporting structure includes features which function to isolate the supported panel from vibrations in the supporting structure. The isolation of the panels leads to reductions in SIL (Speech Interference Level) noise within aircraft cabins. The insert consists of internal and external rigid components separated by a contoured elastomeric component. The elastomeric component is preloaded when installed via a fastener extending through the inner rigid component and attaching to the supporting structure. The outer and inner rigid components are sized such that the inner rigid component will not pass through the outer rigid component, thus providing a safetied installation of the panel. The elastomeric component extends below the bottom of the outer rigid component and provides soft snubbing against the supporting structure during loading of the panels. This allows some level of isolation while restricting motion of the panels.

Abstract: A continuous strip of generally rectangular body portion which is foam filled can be serpentinely wrapped around the handle or steering wheel of a tool or vehicle to isolate the transmission of high frequency vibrations from the user's hands. This will significantly reduce the incidence of occupational disabilities associated with the use of these tools and hand steered vehicles.

Abstract: A controllable brake (20) including a rotor (28) supported by a shaft (30) which is rotatably supported by bushings (42) received in housing (22). A coil assembly (48) creates a magnetic field within a pole piece (32), which is preferably manufactured from a powdered metal material, which preferably has a density of between about 6.8 and 7.0 gm/cm. A magnetically-soft medium is contained within first and second gaps (86, 88) located between pole piece (32) and rotor (28). In one aspect, a magnetic saturation zone (25) reduces the propensity of magnetizing the shaft (30). In another, the pole halves (24, 26) are received in radially-spaced pole pockets (37) formed in the housing (22) and include an axial bias spring (70) to ensure intimate contact. In another aspect, a lip projection (76) traps fluid (23) between the lip projection (76) and shaft (30) and minimizes fluid exposure to the shaft seal (44). In another aspect, cooling fins (55) or a projection (53) restrains rotation of the housing (22).

Abstract: A bushing style mount with low stiffness in two directions oriented with one of the low stiffness directions vertically to provide better isolation. Two elastomeric layers are bonded to two non-parallel surfaces of an inner member, on the one hand, and to a pair of plates on the other. Each of the plates has a contoured, non-planar configuration which increases the axial stiffness of the mount so that the truck cab's lateral motion is minimized. The inner member's non-parallel surfaces are also non-planar, preferably matching the non-planar configuration of the plates, such that the bonded elastomer is deflected into a vee configuration, for example. The inner member with the two elastomeric layers bonded thereto with the two plates bonded, in turn, to the outer faces of the elastomer, form a subassembly that is installed into a generally cylindrical housing. The housing and the outside faces of the plates have a mating contour which provides an alignment feature.

Abstract: The inner periphery of the elastomer portion of a safetied elastomeric sandwich mount assembly is provided with a protrusion that engages the outer periphery of the rigid spacer to hold the three elements of the mount assembly together on either side of the support until the supported member such as an engine or cab of an off-highway vehicle, for example, can be bolted thereto. The protrusion also provides a centering feature that facilitates insertion of the retaining bolt.

Abstract: A hybrid active-passive system (20) for reducing noise within a passenger compartment and vibration of a fuselage of a vehicle, such as an aircraft (turboprop, turbofan, or helicopter). The hybrid active-passive system (20) includes, in combination: an active acoustic producer such as a loudspeaker (35), Active Vibration Absorber (AVA) (34), or active absorber assembly (39) for producing antinoise within the compartment (42), and a passive resonant device, such as a passive Tuned Vibration Absorber (TVA) (36), or passive TVA assembly (37) for controlling vibration of the fuselage or structural supports interconnecting the disturbance source (e.g. power plants (26), propellers (28a), gearbox (57), main rotor (28m), tail rotor (28t)) and the fuselage wall (25).

Abstract: An isolator for use in a hand-held vibrating device for providing optimum vibration isolation by utilizing elastomeric buckling sections which operate in a buckled mode during normal use. The buckled elastomer sections significantly reduce the spring rate within an operating load range thus substantially reducing the vibration transmitted to the user. Six embodiments are shown which utilize buckling sections to enhance vibration isolation along an axial direction of vibration. A first embodiment includes a frustoconical section, while the second employs a W-shaped buckling element. A third embodiment includes use of a tuned fluid inertia which is tuned to substantially coincide with a predominant operating frequency of the vibrating device and produces amplified counter inertial forces to substantially reduce the vibration transmitted to the user, while three other embodiments employ metallic buckling springs.

Abstract: The invention relates to magnetorheological (MR) fluid devices and the process of controlling the force in exercise equipment by utilizing the MR fluid devices. The MR fluid devices include rotary and linear acting varieties and are useful for controlled forces in exercise bicycles, recumbent exercisers, ski machines, rowing machines, and stair stepper machines. The rotary MR fluid device is comprised of a rotor supported by bearings and received within a housing. An MR fluid is received adjacent the rotor and within a cavity in the housing and the MR fluid is controlled by an applied magnetic field to vary the operating torque resistance. Spring biasing the rotor allows for relaxed tolerances. Optimization of the Ri/Ro ratio is described which reduces the size and weight of the device. The linear acting version utilizes simple extensible pumps and an external MR fluid valve to provide a modularized system.

Abstract: A magnetic calendar (20), which may be of the perpetual type, includes a non-ferromagnetic body portion (22) which is preferably rectangular and preferably substantially planar, having a front surface (24) and back surface (26) for abutting a metal surface (38). The front surface (24) of the body portion (22) is divided into a plurality of segments (28) forming a grid-like section (30). The segments (28) may display artwork (58) such as a small pictorial (66), a portion of a large pictorial (64), or a phrase (60). The magnetic pieces (32) adhere to the front surface (24) of the non-ferromagnetic body portion (22) and may include a feature (33) such as indicia (36), an occasion (35), or a holiday (37) affixed thereon. The magnetic pieces (32) may cover at least a portion of the artwork (58).

Abstract: A method and apparatus is described for limiting transient motions between an aircraft power member and aircraft structure. The apparatus incorporates a coupler (20) for use with inertial-type mounts and includes a body portion (21) having a coupler piston (32) telescopically received therein. Upon exceeding a transient relative motion which causes a fluid flow velocity to be exceeded, seat (38) formed on coupler piston (32) interacts with lip (39) on body portion (21) to cause a fluid flow restriction. This method and apparatus restricts and limits transient motions, i.e., acts as a snuffer, to limit further relative motion between an aircraft power member (54) and an aircraft structural member (52). The coupler piston (32) preferably includes a flexible seal (38) formed thereon and orifice (40) therethrough for providing additional throttle-type damping upon snubbing.

Abstract: An elastomeric bumper restricts movement of large objects such as diesel engines to .+-.0.5" along the bumper's axis. The bumper includes a solid elastomeric button, an elastomeric sleeve spaced therefrom by a gap, and a rigid, tight fitting cup which surrounds the sleeve and limits the outward bulging of the elastomer. The button has an axial length which exceeds the length of the sleeve by an amount which defines a first volume of elastomer. That volume is designed to be equal to the volume of the gap. When the movement of the large object has caused the equivalent of the first volume of elastomer to flow into the gap, additional movement of the object is resisted by bulk loading of the elastomer which behaves as an incompressible fluid and resists additional motion with the full weight of the support to which the bumper is attached.

Abstract: A method is described for identifying the primary load path of a particular engine. An elastomeric mount may then be made laterally soft in a first (in the disclosed case, the tangential) direction and more rigid in the direction of the primary load path. Efforts can then be directed to dynamically softening the mount in the primary load path. Specific apparatus may include passive fluid devices, active fluid devices, passive non-fluid devices and active non-fluid devices. In the case of a fluid mount, another feature of the invention is to have an auxiliary fill port of the volume compensator in alignment with at least one and, preferably both, of the primary fill port for the mount and the inertia track to facilitate filling.

Abstract: Actuators for active vibrational energy control systems which are frequency focused. The high-frequency cancellation function is decoupled from the low-frequency cancellation function to enable the size, force, number and placement of the actuators to be optimized. A hybrid system employing structural actuators to cancel low-frequency vibrations and speakers to cancel higher-frequency vibrations is also taught.

Abstract: An active control method and apparatus for controlling vibration or sound wherein the computational burden to adaptively update the control filter within the update model is reduced. The apparatus includes means for producing an input signal for input to the update model and the reduction block, means for generating an error sensor, and an output device for canceling sound and/or vibration at a selected location. The method uses a gradient descent algorithm such as the filtered-x LMS algorithm and replaces the long filter model with a shortened length filter model. Error signal information together with the output information from the shortened length filter model are used to update the coefficients of the control filter according to an update calculation method. The shortened filter model only contains frequency response information at the L frequencies of interest.

Abstract: A system (20) which includes a frequency-dependent decoupler (21) arranged in a series-spring relationship with an actuator (26) for supplying active forces to cancel vibration. The system (20) also includes a spring (28) for providing a primary load path. The system (20) is responsive to at least one sensor (32, 34, 36 or 38) and is controlled via controller (30). The decoupler (26) has greater frequency dependency than the spring (28) and allows the actuator (26) to be effectively decoupled at low frequency, yet coupled at high frequency. This frequency dependent coupling allows the system (20)to accommodate transient static and low frequency loads and motions by allowing motion across the decoupler (21). However, at high frequency, the decoupler (21) becomes stiffer and couples the actuator (26) with the moving members (22) and (24) such that motion across the decoupler (26) is minimized and the actuator (26) becomes more effective at high frequency attenuation.

Abstract: A drive coupling is fail-safed by providing an inner metallic member with a pair of machined opposing flat surfaces that can engage a pair of pins that are positioned in pockets in the intermediate elastomeric member. These pins are anchored in place with respect to the outer housing by staking the ends of the pins, or the like.

Abstract: A single-piece elastomeric mount installed over a plurality of openings has a like plurality of reinforcing plates to permit the elastomeric rib between the plates' edges to flex. The apertures in the mount can then be aligned with holes in a support having wider tolerances on their end positions. The mount may include two sets of plates: an upper load-distribution set and a lower wear-reducing set, each set being bonded to the elastomer.

Abstract: An adjustable length strut having a unique locking device. An annular spring within a housing surrounds an actuator rod. An actuator member engages one end of the annular spring axially compressing it and causing radial bulging resulting in locking the rod in position relative to the housing. Numerous embodiments are disclosed which may replace gas springs in such applications as seat height adjusters, chair arm adjusters and seatback adjusters. An embodiment is disclosed employing a switch to activate and deactivate the actuator member.

Abstract: A dual-stage mounting system having an auxiliary support. A first set of elastomeric mounts connects the vibratory compactor drum to the auxiliary support and a second set of elastomeric mounts interconnect the auxiliary support to the vehicular frame. The dual-stage mounting system reduces by more than 70% the vibration transmitted from the drum to the primary support by a single-stage isolation mounting system thereby extending the life of the vehicle and improving operator comfort.