Abstract: An external activation clutch brake that is controlled by a switch is actuated when a clutch pedal is depressed. A compression spring, torsion spring or hydraulic valve may be used to simulate engagement of a standard clutch brake in which clutch brake squeeze is sensed by the driver. The clutch pedal has first and second phases of movement with the load required to compress the clutch pedal in a first phase being less than the load required to further compress the clutch pedal in a second phase.

Abstract: An embodiment provides a drive train for a medium duty truck. The drive train includes an engine having an engine output member, and a centrifugal clutch. The clutch has a plurality of swing weights and a driving member. The driving member generally defines an axis and is rotatable with the engine output member. The clutch also includes a ramp portion having a generally planar ramped surface portion in selective engagement with at least a portion of the swing weights, and a clutch disk portion for transferring torque from the driving member to a driven member. The clutch is operable between an engaged condition and a disengaged condition. The swing weights are radially moveable with respect to the axis. Radial movement of the swing weights causes axial movement of at least a portion of the clutch between a disengaged position and an engaged position. The swing weights engage only the ramped surface portion when the at least a portion of the clutch is not in the disengaged position.

Abstract: A rotational coupling assembly for transmitting torque between a driving member and a driven member includes a torsionally compliant component having first and second rotary torque transmitting members rotatable relative to one another throughout a first angular distance, and a compliant member that provides a resilient driving connection between the first and second rotary torque transmitting members within the first angular distance. A torque overload protection component is secured for rotation with the driving member and is rotatable relative to the second rotary torque transmitting member throughout a second angular distance. The overload protection component includes a rotation limiting connector adapted to selectively establish a driving connection between the overload protection component and the second rotary torque transmitting member to limit the amount of torque transmitted through the torsionally compliant component.

Abstract: A dual friction clutch assembly for a multiple-ratio transmission comprises separate friction disks of the assembly separately connected to each of two torque input shafts for the transmission. Two torque flow paths for the torque input shafts are defined in part by pre-engaged transmission clutches.

Abstract: A centrifugal clutch assembly is provided that includes a cover module having a pressure plate for applying a clamping force against a friction plate, a moveable plate adapted to rotate with the cover module, but axially displaceable with respect thereto to apply an axial force on the pressure plate through a preloaded plate spring, a fixed plate secured for rotation with the cover module, and a plurality of weights positioned between the moveable plate and the fixed plate that are adapted to move outward under the effects of centrifugal force to cause axial movement in the movable plate and a clamping force on the friction plate. The cover module also includes at least one return spring configured to apply a return force on the weights through the moveable plate, the return force being generally parallel to the axis of rotation of the cover module and independent of weight position.

Abstract: An actuation module of a centrifugal clutch incorporates a plurality of actuating weights mounted on pivot links. The weights pivot radially outwardly under centrifugal forces induced by rotation of the actuation module. One weight is secured to each of the pivot links, and springs counter the radially outward movements of the weights. Each weight defines a slot; a roller is disposed in each of the slots. Each slot defines a pair of spaced walls; each of the rollers is rotatable on an axle secured between one pair of walls. The rollers engage cam ramps that rotate with the module but are axially displaceable with respect thereto for engagement and disengagement of the clutch. Each pair of walls is oriented in direction of pivotal movement of its associated weight. A roller thrust plate is secured between each roller and the wall of the slot spaced farthest away from the pivot link.

Abstract: An actuation module of a centrifugal clutch incorporates a plurality of actuating weights mounted on pivot links. The weights pivot radially outwardly under centrifugal forces induced by rotation of the actuation module. One weight is secured to each of the pivot links, and springs counter the radially outward movements of the weights. Each weight defines a slot; a roller is disposed in each of the slots. Each slot defines a pair of spaced walls; each of the rollers is rotatable on an axle secured between one pair of walls. The rollers engage cam ramps that rotate with the module but are axially displaceable with respect thereto for engagement and disengagement of the clutch. Each pair of walls is oriented in direction of pivotal movement of its associated weight. A roller thrust plate is secured between each roller and the wall of the slot spaced farthest away from the pivot link.