Abstract: A noise and vibration damper for use with a rotatable structure, such as a driveshaft assembly for a vehicular drive train system, includes an inner member, an elastomeric member that extends about the inner member, and an outer member that extends about the elastomeric member. The inner member is formed from a sheet of material that has been deformed to a desired shape, while the outer member is formed from a tube of material having a length that is selected to provide the desired dampening frequency. The natural resonant frequency of the noise and vibration damper can be adjusted by varying either or both of the shape of the inner member or the axial length of the outer member of the noise and vibration damper. In both instances, the weight distribution of the components of the noise and vibration damper is altered.

Abstract: A noise and vibration damper for use with a rotatable structure, such as a driveshaft assembly for a vehicular drive train system, includes an inner member, an elastomeric member that extends about the inner member, and an outer member that extends about the elastomeric member. The inner member is formed from a sheet of material that has been deformed to a desired shape, while the outer member is formed from a tube of material having a length that is selected to provide the desired dampening frequency. The natural resonant frequency of the noise and vibration damper can be adjusted by varying either or both of the shape of the inner member or the axial length of the outer member of the noise and vibration damper. In both instances, the weight distribution of the components of the noise and vibration damper is altered.

Abstract: A two piece cover assembly for protectively covering an end of a component, such as a slip yoke, in a vehicle drive train assembly includes a tubular piece and a cap piece. The tubular piece is hollow and is adapted to fit over and frictionally engage an end portion of the component. A portion of the tubular piece may be deformed to provide such frictional engagement. The cap piece is removably attached to the tubular piece by cooperating retaining structures provided thereon.

Abstract: A noise reduction structure for an aluminum-based driveshaft tube includes a generally cylindrical member having a predetermined length. The noise reduction structure is disposed within a driveshaft tube in a press fit relationship with the inner surface of the tube. In general, the noise reduction structure is positioned within the driveshaft tube at a location where the amplitude of a standing wave caused by the reflection of the sound waves back and forth along the driveshaft tube is at its maximum value. The length of the noise reduction structure may be about 10% or less of the value of the length of the driveshaft tube. In a first embodiment, the noise reduction structure is formed from a polymeric foam material having a density of less than about 10 lb/ft3. Preferably, the material has a density in the range of about 2 lb/ft3 to 10 lb/ft3, and more preferably, in the range of about 3 lb/ft3 to 7 lb/ft3.

Abstract: A method for installing a noise reduction structure within a vehicle driveshaft tube includes the initial step of disposing a reducing sleeve adjacent to a first end of the driveshaft tube. The reducing sleeve may define an inner surface that is tapered from a first diameter, which is slightly larger than the uncompressed outer diameter of the noise reduction structure, to a second diameter, which is approximately equal to the diameter of the first end of the driveshaft tube. Alternatively, the reducing sleeve may define an inner surface that is tapered from a first diameter and then rounded to a second diameter. A source of vacuum is disposed adjacent to a second end of the driveshaft tube, opposite the first end. The source of vacuum may be an accumulator tank and compressor assembly or a venturi arrangement. In any event, the noise reduction structure is disposed within the reducing sleeve and a vacuum is generated such that the vacuum draws the noise reduction structure into the driveshaft tube.

Abstract: A noise reduction structure for a vehicle driveshaft assembly insures that each of the interior chambers of the driveshaft tube is properly vented during use. The noise reduction structure is a solid member having a predetermined length and a cross sectional shape which corresponds generally to the cross sectional shape of the driveshaft tube. Preferably, the noise reduction structure has an outer diameter which is approximately equal to, or slightly larger than, the inner diameter of the driveshaft tube. As such, the noise reduction structure engages the inner surface of the driveshaft tube in a light press fit relationship. Each noise reduction structure has a passageway, groove, or other opening formed therein which extends axially throughout its length. In a preferred embodiment, an axially-extending groove is formed on the outer circumferential surface of the noise reduction structure.