44 results about "Constrained-layer damping" patented technology

A head stack assembly for a disk drive includes a rotary actuator assembly. The rotary actuator assembly includes an actuator body having a bore defining a pivot axis, an actuator arm cantilevered from the actuator body, and a coil portion cantilevered from the actuator body in a direction opposite from the actuator arm. The coil portion includes a coil support, a flat coil supported by the coil support, the flat coil including a coil surface generally perpendicular to the pivot axis, and a constrained layer damper attached to the coil surface. The constrained layer damper includes a stiffening layer having a coil-facing planar surface generally perpendicular to the pivot axis and an adhesive layer positioned between the coil-facing planar surface and the coil surface.

The design and refinement of a tethered hovering platform into a feasible working system is presented. To determine a starting point for the design, a detailed historical search was conducted to find the history and the current state of such technology. Real world current needs are analyzed to produce a mission specification and to drive the preliminary vehicle design. Analysis of environmental conditions and decisions about an initial payload package are made in conjunction with motor and propeller sizing. Initial concept testing to discover feasibility and operational issues was performed; from this, instability issues were discovered. Analyzing these instability issues using known rotorcraft and momentum effects, in conjunction with flight testing, yields possible solutions to the problem. The use of constrained layer dampers as a means of passive stabilization is addressed and suggested as the preferred solution. Testing of passive constrained layer damping verifies the stability of the solution. The system components and manufacturing cost is presented in comparison to current systems using active stabilization.

A method of forming a panel constrained layer damper treatment from a laminate, having a panel and a visco-elastic layer attached thereto, by forming a panel constrained layer damper from the laminate to a predetermined shape is provided. Additionally, the method of the present invention includes attaching the panel constrained layer damper to a substrate to form the panel constrained layer damper treatment. The method may also include subjecting the panel constrained layer damper to heat energy to bond the visco-elastic layer to the substrate. In addition, various methods of attaching the panel constrained layer damper to the substrate are provided.

A payload adapter consists of a body that when hollow includes a plurality of stiffeners—radial and / or circumferential—or alternatively a core for carrying shear loads. The body may include a first annular face sheet, a second annular face sheet and a plurality of stiffeners connecting between the first annular face sheet and the second annular face sheet. The combination of the annular hollow body and the plurality of stiffeners or the same face sheets combined with an in-filled core results in an axial frequency and a lateral (pitch) frequency for the payload adapter that provides superior vibration isolation. Constrained layer damping is incorporated into the design for additional vibration attenuation.

Apparatus and method for damping operational vibration modes of an actuator assembly. The actuator assembly preferably supports a data transducing head adjacent a storage medium in a servo track writing environment. The actuator assembly further supports a circuit assembly comprising circuit board, card or other circuit portion to facilitate electrical communication with the data transducing head. A damping assembly is interposed between the circuit assembly and the actuator assembly to mechanically decouple the circuit assembly from the actuator assembly. Preferably, the damper assembly comprises one or more rigid damper plates and one or more viscoelastic layers therebetween to provide constrain layer damping. As desired, the plates can be provided with progressively larger thickness dimensions in a direction away from the actuator assembly.

Outer arm constrained layer dampers to improve actuator dynamics are disclosed. One embodiment provides a housing and disk pack mounted to the housing and having a plurality of disks that are rotatable relative to the housing. In addition, an actuator is coupled to the housing, the actuator having a plurality of suspensions arms for reaching over the plurality of disks. A first damper is coupled with an outside (or inside) portion of a top outside suspension arm of the plurality of suspensions arms. In addition, a second damper is coupled with an outside (or inside) portion of a bottom suspension arm of the plurality of suspensions arms. In so doing, vibration modes involving deformation of the top suspension arm and the bottom suspension arm are damped.

A voice coil for a voice coil motor of a hard disk drive comprises an inner surface of the voice coil, which bounds a central space of the voice coil. A first outer surface of the voice coil is substantially parallel to a second outer surface of the voice coil. A constrained layer damper is attached to the inner surface of the voice coil by a coupler. The constrained layer damper comprises a first constraining layer coupled to a first surface of a viscoelastic damping layer. A second constraining layer is coupled to a second surface of the viscoelastic damping layer. The constrained layer damper is curved in a direction that is substantially perpendicular to the first outer surface of the voice coil and the second outer surface of the voice coil.

A flex cable assembly for a head stack assembly of a hard disk drive comprises a flex cable for conducting data signals from the head stack assembly to a connector. The flex cable comprises a dynamic loop section between a termination for the head stack assembly and the connector. A constrained layer damper is attached adjacently to an area of the flex cable that is configured to receive the coupler. The constrained layer damper extends into the dynamic loop section of the flex cable.

Outer arm constrained layer dampers to improve actuator dynamics are disclosed. One embodiment provides a housing and disk pack mounted to the housing and having a plurality of disks that are rotatable relative to the housing. In addition, an actuator is coupled to the housing, the actuator having a plurality of suspensions arms for reaching over the plurality of disks. A first damper is coupled with an outside (or inside) portion of a top outside suspension arm of the plurality of suspensions arms. In addition, a second damper is coupled with an outside (or inside) portion of a bottom suspension arm of the plurality of suspensions arms. In so doing, vibration modes involving deformation of the top suspension arm and the bottom suspension arm are damped.

A flex cable assembly for a head stack assembly of a hard disk drive comprises a flex cable for conducting data signals from the head stack assembly to a connector. The flex cable has a dynamic loop section between a termination for the head stack assembly and the connector. The flex cable has a constrained layer damper for attenuating random transient vibration. The constrained layer damper has a symmetrically tapered shape for reducing stress concentration and is coupled with the dynamic loop section of the flex cable adjacent to an area of the flex cable configured for receiving a coupler for coupling the flex cable assembly with the head stack assembly.

A constrained layer damper having a multilayer damping material is provided, as are related methods for making and using the damper. The constrained layer damper features a constraining layer, a carrier layer, a release liner, a viscoelastic layer interposed between the constraining layer and a first surface of the carrier layer, and a silicone pressure-sensitive adhesive interposed between the release liner and a second surface of the carrier layer. The silicone pressure-sensitive adhesive has sufficient tackiness at room temperature to adhere the constrained layer damper, with the release liner removed, to a substrate, such as a metallic substrate. The constrained layer damper has a peak damping temperature value in a range of about 50° C. to about 100° C.

A fan blade having a damping system is provided. The fan blade comprising: a fan blade body having one or more compartments within the fan blade body; a damping material located within at least one of the one or more compartments; one or more partial ribs originating at the fan blade body and extending into at least one of the one or more compartments, wherein each of the one or more partial ribs terminate at a distal end; and one or more damping plates, wherein each of the one or more damping plates are attached to a distal end of a partial rib, wherein the damping material is located between the damping plate and the fan blade body.