Abstract: In an aspect an isolation device is provided, comprising a hub that is connectable to a shaft; a pulley that is rotatable relative to the hub; at least one isolation spring positioned to transfer torque between the hub and the pulley, wherein each of the at least one isolation spring is an arcuate helical compression spring having an isolation spring axis that is arcuate; and a spring shell that is monolithic and that receives the at least one isolation spring and transfers torque between the at least one isolation spring and the pulley. The spring shell surrounds more than 180 degrees of the at least one isolation spring in a plane that is perpendicular to the isolation spring axis.

Abstract: A decoupler having an input hub, an output member, a one-way clutch, and at least one isolation spring. Rotary power is transmitted in a predetermined rotational direction from the input hub, through the one-way clutch, through the isolation spring and to the output member. A method for forming a decoupler is also provided.

Abstract: In an aspect, an isolator is provided for isolating torsional vibration between a crankshaft of an engine and an endless drive member. The isolator includes a driver drivable by the crankshaft, a pulley that is engageable with an endless drive member, at least one isolation spring that is positioned to transfer forces between the driver and the pulley and to isolate torsional vibrations in the driver and the pulley from one another, and a damping structure configured to frictionally resist relative movement between the driver and the pulley beyond a selected relative threshold angle, and to permit relative movement between the driver and the pulley within the selected relative threshold angle without frictional resistance from the damping structure.

Abstract: In an aspect, an isolator is provided, comprising a hub, a pulley, an isolation spring and a transition spring. The hub defines an axis and is connectable to a rotatable shaft of a rotary device. The pulley is rotatably mounted to the hub. The isolation spring and transition spring act in series in a torque path between the pulley and the hub. The isolation spring has a first spring rate. The transition spring has a second spring rate that is lower than the first spring rate.

Abstract: In an aspect, a spring assembly is provided for an isolator, and includes first and second helical compression springs, a retainer and a spring housing. The first helical compression spring has a central aperture and has a first end and a second end. The second helical compression spring having a central aperture and having a first end and a second end, wherein the second spring is coaxial with and nested within the first spring. The retainer has a base and a post that extends from the base into the central aperture at the first end of the second helical spring. The spring housing that has an interior space in which the first and second springs are positioned, and further includes a base-engaging aperture that holds the base of the retainer. The spring housing includes a drive wall that is engaged with the first ends of the first and second springs.

Abstract: In an aspect an isolation device is provided, comprising a hub that is connectable to a shaft; a pulley that is rotatable relative to the hub; at least one isolation spring positioned to transfer torque between the hub and the pulley, wherein each of the at least one isolation spring is an arcuate helical compression spring having an isolation spring axis that is arcuate; and a spring shell that is monolithic and that receives the at least one isolation spring and transfers torque between the at least one isolation spring and the pulley. The spring shell surrounds more than 180 degrees of the at least one isolation spring in a plane that is perpendicular to the isolation spring axis.

Abstract: A decoupler having an input hub, an output member, a one-way clutch, and at least one isolation spring. Rotary power is transmitted in a predetermined rotational direction from the input hub, through the one-way clutch, through the isolation spring and to the output member. A method for forming a decoupler is also provided.

Abstract: A decoupler having an input hub, an output member, a one-way clutch, and at least one isolation spring. Rotary power is transmitted in a predetermined rotational direction from the input hub, through the one-way clutch, through the isolation spring and to the output member. A method for forming a decoupler is also provided.

Abstract: In an aspect, a decoupler is provided, and included a driver having a clutch surface a hub that is disposed within the driver, and at least one torsionally-compliant member and a wrap spring clutch that are disposed in series between the hub and the clutch surface. The driver comprises a pulley and a cover that is received into a cavity in the pulley. The pulley has a belt-engagement surface and is fixedly coupled to the cover for rotation therewith. The cover defines the clutch surface.

Abstract: In an aspect, an isolator is provided, comprising a hub, a pulley, an isolation spring and a transition spring. The hub defines an axis and is connectable to a rotatable shaft of a rotary device. The pulley is rotatably mounted to the hub. The isolation spring and transition spring act in series in a torque path between the pulley and the hub. The isolation spring has a first spring rate. The transition spring has a second spring rate that is lower than the first spring rate.

Abstract: In an aspect, an isolator is provided for isolating torsional vibration between a crankshaft of an engine and an endless drive member. The isolator includes a driver drivable by the crankshaft, a pulley that is engageable with an endless drive member, at least one isolation spring that is positioned to transfer forces between the driver and the pulley and to isolate torsional vibrations in the driver and the pulley from one another, and a damping structure configured to frictionally resist relative movement between the driver and the pulley beyond a selected relative threshold angle, and to permit relative movement between the driver and the pulley within the selected relative threshold angle without frictional resistance from the damping structure.

Abstract: A clutched device that includes a driving member, a driven member and a clutch assembly that is disposed between the driving and driven members. The clutch assembly includes a carrier, a wrap spring and a spacer. The carrier is configured to coupled the wrap spring to one of the driving and driven members to permit the transmission of rotary power there between. The spacer is configured to limit elongation of the wrap spring in an axial direction.

Abstract: In an aspect, a spring assembly is provided for an isolator, and includes first and second helical compression springs, a retainer and a spring housing. The first helical compression spring has a central aperture and has a first end and a second end. The second helical compression spring having a central aperture and having a first end and a second end, wherein the second spring is coaxial with and nested within the first spring. The retainer has a base and a post that extends from the base into the central aperture at the first end of the second helical spring. The spring housing that has an interior space in which the first and second springs are positioned, and further includes a base-engaging aperture that holds the base of the retainer. The spring housing includes a drive wall that is engaged with the first ends of the first and second springs.

Abstract: A decoupler that includes a drive member, a hub and an isolator that is configured to transmit rotary power between the drive member and the hub in a predetermined rotational direction. The isolator includes a wrap spring, a plurality of helical coil springs, and a carrier assembly. The wrap spring includes a plurality of helical coils and a proximal end. The helical coil springs are disposed between the hub and the carrier assembly. The carrier assembly includes a carrier plate and a spring shell. The carrier plate has a plate member with a rim and a spring groove. The rim abuts an axial end of the wrap spring. The proximal end of the wrap spring is received in the spring groove. The spring shell is assembled to the carrier plate and has a toric inner surface into which the helical coil springs are received.

Abstract: In an aspect, a decoupler is provided, and included a driver having a clutch surface a hub that is disposed within the driver, and at least one torsionally-compliant member and a wrap spring clutch that are disposed in series between the hub and the clutch surface. The driver comprises a pulley and a cover that is received into a cavity in the pulley. The pulley has a belt-engagement surface and is fixedly coupled to the cover for rotation therewith. The cover defines the clutch surface.

Abstract: An engine starter that employs a clutch between a flywheel or flex plate and a plate structure that is configured to receive rotary power from a starter motor through a transmission. The transmission may include ring and pinion gears or a belt that transmits rotary power between pulleys.

Abstract: A decoupler that includes a drive member, a hub and an isolator that is configured to transmit rotary power between the drive member and the hub in a predetermined rotational direction. The isolator includes a wrap spring, a plurality of helical coil springs, and a carrier assembly. The wrap spring includes a plurality of helical coils and a proximal end. The helical coil springs are disposed between the hub and the carrier assembly. The carrier assembly includes a carrier plate and a spring shell. The carrier plate has a plate member with a rim and a spring groove. The rim abuts an axial end of the wrap spring. The proximal end of the wrap spring is received in the spring groove. The spring shell is assembled to the carrier plate and has a toric inner surface into which the helical coil springs are received.

Abstract: A decoupler having a hub, a drive member and an isolator. The drive member is disposed about the hub for rotation about a rotational axis and includes an inner clutch surface. The isolator couples the hub and the drive member and includes a carrier, a plurality of arcuate springs, and a wrap spring. The carrier is received between the hub and the drive member and includes a carrier member, which defines a pair of apertures, and a pair of reaction blocks that are mounted in the apertures. The arcuate springs are mounted in the carrier member and are disposed between the hub and an associated one of the reaction blocks. The wrap spring has an end and a plurality of helical coils that are engaged to the inner clutch surface of the drive member. The end has an end face that is abutted against one of the reaction blocks.

Abstract: A tensioner for tensioning flexible drives employs an extruded shaft which can provide a relatively complex cross sectional shape to provide anti-rotation features to inhibit rotation of a pivot bushing located on the shaft. The pivot bushing has a frustoconical outer shape, as does the pivot surface of the hub of the tensioner arm which pivots on the pivot bushing. A dampening spring urges the pivot bushing towards the tensioner arm's pivot surface, providing for wear compensation and for dampening. The degree of dampening which is generated between the pivot bushing and the tensioner hub can be selected in a variety of manners: by varying the spring force; by changing the effective contact surface area between the pivot bushing and pivot surface; and/or by changing the coefficient of friction between the pivot bushing and the pivot surface.

Abstract: A clutched device that includes a driving member, a driven member and a clutch assembly that is disposed between the driving and driven members. The clutch assembly includes a carrier, a wrap spring and a spacer. The carrier is configured to coupled the wrap spring to one of the driving and driven members to permit the transmission of rotary power there between. The spacer is configured to limit elongation of the wrap spring in an axial direction.