An accessory drive tuning device with a torsion spring for angular vibration isolation and having a spring pocket that frictionally engages the end of the torsion spring. The engagement may be with a wedge-shape on either the spring end or the pocket or both, adapted so that the spring end wedges into the pocket. The engagement may be by interference fit. One or both ends of the spring may be engaged in respective pockets.

Disposable torque-limiting devices having an upper shank component with a torque-limiting interface, a lower shank component with a torque-limiting interface, and a spring element. Torque-limiting interfaces having a plurality of undulations arranged around an axial bore or drive socket and separated by a plurality of transition regions, with each undulation having an upslope, a peak, and a downslope. The torque-limiting interfaces are configured to engage and disengage to provide torque transmission with predetermined torque limits at various rotational speeds and for amounts of actuations while remaining within a specified operational range. The encasement provides mounts for a tool and for a drive shaft which may be connected to a powered device.

Disposable torque-limiting mechanisms with an upper shank component with a torque-limiting interface, a lower shank component with a torque-limiting interface, and a rubbery spring material biasing element. Torque-limiting interfaces having a plurality of undulations arranged around an axial bore or drive socket and separated by a plurality of transition regions, with each undulation having an upslope, a peak, and a downslope. The torque-limiting interfaces are configured to engage and disengage to provide torque transmission with predetermined torque limits at various rotational speeds and for amounts of actuations while remaining within a specified operational range.

A brake or a clutch includes a central shaft, an output-side threaded driver, an output brake plate, an input brake plate, and an input-side threaded driver. The output-side threaded driver and the input-side threaded driver are rotationally locked to the central shaft, such as by splines. The output-side threaded driver is threaded to the output brake plate and the input-side threaded driver is threaded to the input brake plate. The output brake plate is threaded to the input brake plate in a direction opposite the threaded engagement of the drivers to the brake plates. The brake or clutch may include two stator plates and three friction discs located between the output brake plate and the input brake plate.

Disposable torque-limiting mechanisms with an upper shank component with a torque-limiting interface, a lower shank component with a torque-limiting interface, and a rubbery spring material biasing element. Torque-limiting interfaces having a plurality of undulations arranged around an axial bore or drive socket and separated by a plurality of transition regions, with each undulation having an upslope, a peak, and a downslope. The torque-limiting interfaces are configured to engage and disengage to provide torque transmission with predetermined torque limits at various rotational speeds and for amounts of actuations while remaining within a specified operational range.

Disposable torque-limiting devices having an upper shank component with a torque-limiting interface, a lower shank component with a torque-limiting interface, and a spring element. Torque-limiting interfaces having a plurality of undulations arranged around an axial bore or drive socket and separated by a plurality of transition regions, with each undulation having an upslope, a peak, and a downslope. The torque-limiting interfaces are configured to engage and disengage to provide torque transmission with predetermined torque limits at various rotational speeds and for amounts of actuations while remaining within a specified operational range. The encasement provides mounts for a tool and for a drive shaft which may be connected to a powered device.