Abstract: A crankshaft damper-isolator that includes a hub having an outer radial surface and an outermost radial surface spaced radially outward from the outer radial surface and thereby defining an annular receptacle therebetween, a pulley body having a belt engaging portion radially-concentric about the hub and a face guard that terminates in a central bore seated about the outer radial surface of the hub, a damper assembly disposed between the outermost radial surface of the hub and belt engaging portion of the pulley body, a back plate fastened to the hub, a first elastomeric isolator member encapsulated and interlocked in compression between the annular receptacle of the hub and a front face of the face guard of the pulley body, and a second elastomeric isolator member encapsulated and interlocked in compression between the back plate and a back face of the face guard of the pulley body.

Abstract: Two-part hubs for torsional vibration dampers are disclosed that have a main body made of a softer material than a seal nose and do not require a welded joint to join them together. The main body has a plate defining a front face and a back face, an annular core extending axially outward from the back face of the plate and defining an innermost, outer radial surface and a first bore through the main body, and an outermost, radial, elastomer-receiving surface spaced apart from the innermost outer radial surface by the plate. The seal nose is mated to the innermost, outer radial surface of the annular core and mechanically engaged with the main body for rotation together. Torsional vibration dampers that include the two-part hubs are also disclosed, as well as a front end accessory drive including the same, and methods of manufacturing the two-part hubs.

Abstract: Elastomer members for a torsional vibration damper, methods of making the same, and torsional vibration dampers having the elastomer members are disclosed. The elastomer members have a first major surface and an opposing second major surface with opposing side joining the first major surface to the second major surface, have a median sagittal plane extending parallel to the first major surface and the second major surface, and a transverse plane perpendicular to the median sagittal plane. In a cross-sectional geometry in a plane bisecting the median sagittal plane and the transverse plane, a thickness of the elastomer member changes along the median sagittal plane in a direction parallel to the transverse plane with a first thickness at both opposing sides and a second thickness at the transverse plane, where the second thickness is greater than the first thicknesses.

Abstract: Radial vibration dampers have an inertia member defining an annular channel having (i) a radially facing, open face; (ii) a bottom surface; and (iii) interior, opposing surfaces. The interior, opposing surfaces are each angled outward away from a central transverse plane through the inertia member at an angle in a range from zero degrees to at most 45 degrees. A spring damper member is seated in the annular channel to a selected depth that defines a damper gap between a radial inner surface of the spring damper member and the bottom surface of the annular channel and defines a clearance gap between the shaft and the inertia member. A tuning ratio of the clearance gap to the selected depth is in a range of about 1:1.5 to about 1:0.5.

Abstract: Torsional vibration dampers (TVDs) having a plurality of spokes that are asymmetric by having a changing spoke thickness in the angular direction with the greatest thickness at the position where the belt torque and the dynamic torque of the TVD act in unison are disclosed. The spokes, which connect a central member to a peripheral rim, include an asymmetrical thickness in an angular direction, as evidenced by a cross-section view transverse to a radial length of each of the plurality of spokes. Engine systems having one of the disclosed TVDs mounted to a shaft are also disclosed, for example a TVD mounted to a crankshaft.

Abstract: Torsional vibration dampers are disclosed that have a hub defining a plurality of fastener-receiving openings and an inertia member concentric about and spaced a radial distance apart from a shaft-receiving member of the hub and having a plurality of receptacles defining a bore oriented axially. Each receptacle aligns with one of the plurality of fastener-receiving openings, and receives one of a plurality of elastomeric rings with a fastener seated therein and received in the fastener-receiving openings to operatively connect the inertia member to the hub through compression of the elastomeric rings. The height of each elastomeric ring is greater than the axial width of the receptacles, and compression of the elastomeric rings deforms each radially into a first gap between the hub and the inertia member and a second gap between the inertia member and the fastener, thereby axially locking the inertia member to the hub for rotation together.

Abstract: Torsional vibration dampers having a dual spring-dashpot system are disclosed that result in a lightweight hub and a lightweight inertia ring, which is concentric about the hub. The hub has a two-piece construction: a central hub defining an innermost sleeve that defines a bore for receiving a shaft; and a monolithic, generally-annular spoke defining an outermost ring concentric about and spaced radially outward from the central hub portion. A first elastomer member, which acts as a primary spring to damp torsional vibrations, is positioned concentrically against an inner surface or an outer surface of the outermost ring of the hub with the inertia ring concentrically positioned against the first elastomer member. A second elastomer member is positioned between and operatively couples the central hub to the annular spoke, thereby attributing a flexibility to the hub.

Abstract: Damper-isolators are disclosed that have a hub defining a bore for receiving a shaft, a pulley body mated to the hub to collectively define a magnet track that is concentric about the bore, a damper assembly operatively disposed between the hub and a belt engaging portion of the pulley body, a first magnet positioned within the magnet track and connected to the hub for rotation therewith, and a second magnet positioned within the magnet track and connected to the pulley body for rotation therewith. The first magnet and the second magnet are positioned with like polarities facing one another. A front end accessory drive system having one of the damper-isolators is also disclosed.

Abstract: Self-aligning pulleys are disclosed that have a hub, a pulley body concentric about the hub and spaced a distance apart therefrom to define an annular gap, and an annular compliant member disposed in the annular gap between the hub and the pulley body to thereby operatively couple the pulley body to the hub for rotation therewith. The annular compliant member is three-dimensionally compliant to allow the pulley body to adjust in one or more of an axial orientation and a conical orientation relative to the hub to correct misalignments of the hub within a system of pulleys and a belt.

Abstract: Torsional vibration dampers having a hub integral with a pulley body for rotation therewith and at least an annular first elastomeric member seated on the pulley body between the outer belt engaging surface and the hub and held thereagainst for rotation therewith by a first inertia ring connected to the pulley body are disclosed. The torsional vibration dampers may also include an annular second elastomeric member seated on the pulley body, on a side opposite the annular first elastomeric member, between the outer belt engaging surface and the hub and held thereagainst for rotation therewith by a second inertia ring connected to the pulley body or seated on the first inertia member, on a side opposite the first elastomeric member, between the first inertia member and a front end cap, where the front end cap compresses the second elastomeric member against the first inertia member.

Abstract: Torsional vibration dampers for rotating shafts are disclosed that have a hub or a hub portion of a pulley-hub monolithic body that has an innermost sleeve defining a bore, an outermost ring concentric with and spaced radially outward from the innermost sleeve, and a plurality of spokes connecting the innermost sleeve to the outermost ring that each have torsional flexibility to act as a first spring to attenuate torsional vibrations. The dampers include an elastomeric member positioned concentrically against the outermost ring or the innermost sleeve of the hub, where the elastomeric member acts as a second spring to attenuate torsional vibrations, and an inertia member positioned concentrically against the elastomeric member, which places the first spring and second spring in series. The dampers may be crankshaft, driveline, or direct drive dampers, and the equivalent spring rate for the first and second springs is governed by the elastomeric member.

Abstract: Torsional vibration dampers having isolator members (crankshaft damper-isolators) are disclosed that include a hub defining an annular receptacle, a pulley body having a belt engaging surface, a damper assembly disposed between an outermost radial surface of the hub and the pulley body, an isolator member seated in the annular receptacle of the hub, and a slide bearing disposed between an outer radial surface of the hub and the sleeve of the pulley body. The isolator member is engaged with both the hub and the pulley body for rotation therewith when the hub and pulley body rotate at the same speed and when the hub rotates relative to the pulley body. The isolator member may be an elastomeric isolator or a torsion spring isolator. The slide bearing axially retains the pulley body to the hub and allows the pulley body to rotate relative to the hub.

Abstract: A torsional vibration damper is disclosed. The torsional vibration damper comprises a first member having a radially outer surface that comprises a central concave section axially between convex sections and a second member having a radially inner surface that comprises a central convex section axially between concave sections and that opposes said radially outer surface. The radially outer surface and said radially inner surface are separated by a radial gap that defines a cross-sectional profile having an axial center and axial ends, and wherein said radial gap increases in thickness from said axial center to each said axial end of said cross-sectional profile. Alternatively, the first member may include a central convex section axially between concave sections and the second member may include a central concave section between convex section.

Abstract: Torsional vibration dampers (TVDs) having a plurality of spokes designed to withstand both torsional and bending forces and vibrations are disclosed. The spokes, which connect a central member to a peripheral rim, include a first end coupled to an outer radial surface of the central member; a second end coupled to an inner radial surface of the rim; and four concave surfaces extending between the first end and the second end. The concave surfaces may be concave from the first end to the second end and may also be concave laterally from front to back or side to side. A TVD having a hub with spokes having one or more concave surfaces is also disclosed herein. A method of designing the spokes for the hub is also disclosed.

Abstract: Radial vibration dampers (RVD's) press-fittable to a shaft and shaft systems incorporating RVD's are disclosed herein. The RVD's include a first inertia member and a second inertia member fixedly connected to one another to define an annular channel having a radially facing, open side and a spring damper material seated in the annular chamber and axially compressed between the two inertia members. The spring damper material has a compressible portion protruding from the radially facing, open side so that, when the compressible portion is compressed against a shaft, the spring damper material defines a gap between the shaft and the inertia members. The RVD may be press-fittable inside a hollow shaft or to the outside of a hollow or solid shaft. The RVD's disclosed herein have first vibration mode shapes that are radial in nature and decoupled from latter vibration modes.

Abstract: Elastomer members for a torsional vibration damper, methods of making the same, and torsional vibration dampers having the elastomer members are disclosed. The elastomer members have a first major surface and an opposing second major surface with opposing side joining the first major surface to the second major surface, have a median sagittal plane extending parallel to the first major surface and the second major surface, and a transverse plane perpendicular to the median sagittal plane. In a cross-sectional geometry in a plane bisecting the median sagittal plane and the transverse plane, a thickness of the elastomer member changes along the median sagittal plane in a direction parallel to the transverse plane with a first thickness at both opposing sides and a second thickness at the transverse plane, where the second thickness is greater than the first thicknesses.

Abstract: Damper-isolators are disclosed that have a hub defining a bore for receiving a shaft, a pulley body mated to the hub to collectively define a magnet track that is concentric about the bore, a damper assembly operatively disposed between the hub and a belt engaging portion of the pulley body, a first magnet positioned within the magnet track and connected to the hub for rotation therewith, and a second magnet positioned within the magnet track and connected to the pulley body for rotation therewith. The first magnet and the second magnet are positioned with like polarities facing one another. A front end accessory drive system having one of the damper-isolators is also disclosed.

Abstract: Mating components that are mateable to another component to share the same axis of rotation, assemblies including the mating component mated to another component, and methods of mating them together are disclosed. The mating component includes a hub having an engaging portion defining an endless channel recessed therein. The endless channel has a surface that defines one or more trenches therein and an elastomeric band seated against that surface in an uncompressed state. The elastomeric band has an outermost dimension relative to the endless channel that is larger than the inner or outer dimension defined by the engaging portion of the hub and thereby defines an unchanneled portion of the elastomeric band, which has a volume that is equal to or less than the total volume of the one or more trenches.

Abstract: Torsional vibration dampers are disclosed that have a hub having a plate extending radially outward about a shaft-receiving member, a first portion of an inertia member defining a back face and a bore therethrough and having an annular flange concentric about the axis of rotation, a first elastomeric member and a second elastomeric member positioned against opposite sides of the plate, and a second portion of the inertia member fastened to the first portion of the inertia member by one or more fasteners, thereby placing the first and second elastomeric members in compression. The shaft-receiving member of the hub is positioned in the bore with the plate of the hub spaced a distance from an interior surface of the annular flange, and the plate of the hub and the interior surfaces of each of the first and second portions of the inertia member facing the plate define dual common vertices.

Abstract: Torsional vibration dampers are disclosed that include a monolithic body having an axis of rotation, an innermost annular wall defining a bore therethrough for receiving a shaft, and an outer annular wall concentric about the axis of rotation and spaced radially outward relative to the innermost annular wall, an inertia member concentric about the axis of rotation and positioned radially inward relative to the outer annual wall, the inertia member having an inner surface facing the axis of rotation and an outer surface facing the outermost annular wall, a first elastomer member seated against the inner surface of the inertia member, and a second elastomer member seated against the outer surface of the inertia member and in between the inertia member and the outer annular wall. The first and second elastomer members operably couple the inertia member to the monolithic body for rotation therewith.