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 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 decoupler having an output member, a one-way clutch, a spring and a spring limiter. The spring is disposed between an output portion of the one-way clutch and the output member to bias the output portion in a predetermined rotational direction relative to the output member. The spring limiter can be configured to lock an output of the one-way clutch to the output member to transmit rotary power between the one-way clutch and the output member without stressing the spring beyond a predetermined point and/or to limit rotational movement of the output portion and an associated end of the spring relative to the output member in the predetermined rotational direction. A method for operating a decoupler is also provided.

Abstract: A one way isolator for high torque devices, such as alternator-starters, driven by a flexible drive means includes a hub and a sheave each of which includes at least one stop member. The hub and sheave are linked by a isolating spring and, via a bearing and/or bushing, can rotate with respect to each other to provide isolation, through the spring, from torque variations when torque is transferred from the flexible drive means to the device. When substantial amounts of torque are transferred from the device to the flexible drive means, the sheave rotates with respect to the hub to bring the stop members into contact such that the isolator then acts like a solid pulley to facilitate the transfer of the torque from the device.

Abstract: An overrunning accessory decoupler with a locking mechanism provides the desired overrunning accessory decoupler functionality and also permits torque to be transferred from the accessory to which the decoupler is installed to the drive of the engine when desired. In one embodiment, the decoupler includes a locking mechanism that is controlled by centrifugal forces developed in the decoupler to lock the decoupler to permit the accessory to transfer torque to the drive to start or boost the engine. In another embodiment, the decoupler locking mechanism includes an electromagnet that can be energized to lock and/or unlock the decoupler.

Abstract: A tensioner operable to substantially maintain a specified tension in a flexible drive, such as a belt or chain, includes a spring, mounted laterally to the pivot shaft of the tensioner, which biases the tensioner arm towards the flexible drive. The spring is arcuate in shape and is maintained in a correspondingly arc-shaped spring retainer on a mounting plate of the tensioner. The arcuate shape of the spring and spring guide on the tensioner arm follows as the tensioner arm pivots towards and away from the flexible drive. The tensioner also has a wear take up mechanism to maintain the friction bushing in continuous engagement with the tensioner arm.

Abstract: A decoupler assembly is provided for allowing an alternator to be rotatably driven by a serpentine belt in an engine of an automotive vehicle and for allowing the speed of the belt to oscillate relative to the alternator. A hub is fixedly carried by a drive shaft from the alternator for rotation therewith. A pulley is rotatably journaled to the hub by a ball bearing assembly. A bare, helical clutch spring is operatively coupled between the hub and pulley for transferring rotational movement from the pulley to the hub during acceleration of the pulley relative to the hub by the serpentine belt and for allowing the hub to overrun the pulley during deceleration of the pulley relative to the hub. A torque limiter, preferably a spring or sleeve, is wrapped about the torsion spring limiting outward expansion of the torsion spring and isolating the torsion spring from torques above a predetermined limit.

Abstract: A decoupler assembly with a torsional damping system and a torque limiter. The torsional damping system has a torsion spring that facilitates transfer of rotary power into a hub. The torque limiter is wrapped about the torsion spring and radially expands with the torsion spring as a magnitude of the rotary power transmitted through the torsion spring increases. Contact between the torque limiter and another structure in the decoupler assembly halts radial expansion of the torsion spring.

Abstract: A decoupler assembly that includes a hub, a drive member disposed about the hub, and a clutch coupling the hub and the drive member. The drive member is disposed about the hub for rotation about a rotational axis and includes an inner clutch surface. The clutch includes a carrier, a plurality of arcuate springs, and a wrap spring. The carrier is received between the hub and the drive member. The arcuate springs are mounted to the carrier and are configured to transmit rotary power between the carrier and the hub. The wrap spring includes a proximal end, which is drivingly coupled to the carrier, and a plurality of helical coils that are engaged to the inner clutch surface of the drive member.

Abstract: A decoupler assembly is provided for allowing an alternator to be rotatably driven by a serpentine belt in an engine of an automotive vehicle and for allowing the speed of the belt to oscillate relative to the alternator. A hub is fixedly carried by a drive shaft from the alternator for rotation therewith. A pulley is rotatably journaled to the hub by a ball bearing assembly. A bare, helical clutch spring is operatively coupled between the hub and pulley for transferring rotational movement from the pulley to the hub during acceleration of the pulley relative to the hub by the serpentine belt and for allowing the hub to overrun the pulley during deceleration of the pulley relative to the hub. A torque limiter, preferably a spring or sleeve, is wrapped about the torsion limiting outward expansion of the torsion isolating the torsion spring from torques above a predetermined limit.

Abstract: A tensioner in accordance with the present invention employs a spindle and a tensioner arm which are preferably manufactured by a suitable manufacturing process, such as die casting, negating a requirement for machining operations. The biasing spring of the tensioner is wound with wire having a non-circular cross section to increase the spring force of the spring compared to a similar spring wound with wire of circular cross section and, as the tensioner arm is moved away from the flexible drive, the diameter of the biasing spring expands and the coils press a dampening shoe into contact with a wall of the tensioner arm producing a dampening force. The tensioner is simple to assemble and requires a relatively small package volume for the biasing force it can produce.

Abstract: A decoupler assembly is provided for allowing an alternator to be rotatably driven by a serpentine belt in an engine of an automotive vehicle and for allowing the speed of the belt to oscillate relative to the alternator. A hub is fixedly carried by a drive shaft from the alternator for rotation therewith. A pulley is rotatably journaled to the hub by a ball bearing assembly. A bare, helical clutch spring is operatively coupled between the hub and pulley for transferring rotational movement from the pulley to the hub during acceleration of the pulley relative to the hub by the serpentine belt and for allowing the hub to overrun the pulley during deceleration of the pulley relative to the hub. A torque limiter, preferably a spring or sleeve, is wrapped about the torsion limiting outward expansion of the torsion isolating the torsion spring from torques above a predetermined limit.

Abstract: A decoupler having an output member, a one-way clutch, a spring and a spring limiter. The spring is disposed between an output portion of the one-way clutch and the output member to bias the output portion in a predetermined rotational direction relative to the output member. The spring limiter can be configured to lock an output of the one-way clutch to the output member to transmit rotary power between the one-way clutch and the output member without stressing the spring beyond a predetermined point and/or to limit rotational movement of the output portion and an associated end of the spring relative to the output member in the predetermined rotational direction. A method for operating a decoupler is also provided.

Abstract: A driven accessory having a clutch that permits selective operation of an accessory portion. The clutch employs rotational inertia to control driving engagement of a wrap spring to an interior clutch surface on a drive member and/or driving disengagement of the wrap spring from the interior clutch surface.

Abstract: A decoupler assembly for transferring rotary movement between an engine driven shaft and a serpentine belt. The decoupler includes a hub configured to be assembled to the shaft. The hub has a helical first slot formed therein. A pulley is rotatably coupled to the hub. A carrier is mounted on the hub and includes a helical second slot formed therein, as well as an anti-ramp up boss formed thereon. A thrust plate is fixed to the hub and has a slot formed therein. A torsion spring is compressed between a hub end retained in the helical first slot and a carrier end retained in the helical second slot for transferring torque between the hub and carrier. The anti-ramp up boss travels within the slot formed in the thrust plate for limiting rotation between the carrier and thrust plate and preventing rotation of the torsion spring relative to the hub and carrier.

Abstract: An overrunning accessory decoupler with a locking mechanism provides the desired overrunning accessory decoupler functionality and also permits torque to be transferred from the accessory to which the decoupler is installed to the drive of the engine when desired. In one embodiment, the decoupler includes a locking mechanism that is controlled by centrifugal forces developed in the decoupler to lock the decoupler to permit the accessory to transfer torque to the drive to start or boost the engine. In another embodiment, the decoupler locking mechanism includes an electromagnet that can be energized to lock and/or unlock the decoupler.

Abstract: A decoupler assembly that includes a hub, a drive member disposed about the hub, and a clutch coupling the hub and the drive member. The drive member is disposed about the hub for rotation about a rotational axis and includes an inner clutch surface. The clutch includes a carrier, a plurality of arcuate springs, and a wrap spring. The carrier is received between the hub and the drive member. The arcuate springs are mounted to the carrier and are configured to transmit rotary power between the carrier and the hub. The wrap spring includes a proximal end, which is drivingly coupled to the carrier, and a plurality of helical coils that are engaged to the inner clutch surface of the drive member.

Abstract: A decoupler assembly (20) is provided for transferring rotational torque between a drive shaft (16) and a drive belt (18) of an automotive engine. The decoupler assembly includes a drive hub (40) configured to be fixedly secured to the drive shaft. A pulley (22) is rotatably coupled to the drive hub (40) and adapted to be drivingly engaged with the belt (18). A spring shell (70, 100) is operatively coupled between the drive hub and the pulley for selective rotation therewith and a biasing member (130) is operatively coupled between the spring shell and the drive hub for isolating oscillatory vibrations between the drive hub and the pulley caused by rotation of the drive shaft. A clutch element (140) is seated between the spring shell (70, 100) and the pulley (22) for selectively transferring rotational torque from the drive hub to the pulley.

Abstract: A dust shield to inhibit the ingress of foreign materials into a pulley bearing is disclosed as is a pulley including such a dust shield. The dust shield is press fit to one side of the bearing such that it is captive during assembly and/or installation of the pulley. A second dust shield can be provided on the opposite side of the bearing to further inhibit the ingress of foreign materials. Preferably, at least one of the dust shields includes a bolt retention feature which holds an installation bolt captive to the pulley prior to installation. The dust shields can be fabricated from selected materials with desired thermal characteristics to insulate the bearing from sources of undesired heat and/or to assist the removal of waste heat from the bearing.

Abstract: A one way isolator for high torque devices, such as alternator-starters, driven by a flexible drive means includes a hub and a sheave each of which includes at least one stop member. The hub and sheave are linked by a isolating spring and, via a bearing and/or bushing, can rotate with respect to each other to provide isolation, through the spring, from torque variations when torque is transferred from the flexible drive means to the device. When substantial amounts of torque are transferred from the device to the flexible drive means, the sheave rotates with respect to the hub to bring the stop members into contact such that the isolator then acts like a solid pulley to facilitate the transfer of the torque from the device.