Abstract: A centrifugal clutch assembly includes a clutch cover attachable to a rotatable input member. Friction plates are clamped between pressure plates in response to rotation of the clutch assembly. Rotation of the clutch assembly causes at least one centrifugal weight to move radially outward to force the pressure plates against the friction plates. The radial position of the centrifugal weights is modified to tailor clutch actuation. This modification of centrifugal weight position causes a corresponding change to engagement characteristics of the clutch assembly allowing clutch actuation to be tailored to operating conditions.

Abstract: A vehicle power train system includes an engine, a transmission, and a centrifugal clutch assembly that selectively couples an engine output shaft to a transmission input shaft in response to an operator input. An operator selects a desired vehicle-operating mode by actuating a shift lever or shift switch from a gear selection device. The gear selection device indicates many different operating modes and includes a low-speed maneuvering mode that is selected for low-speed operations such as coupling a truck to a trailer, or positioning a truck and/or trailer in relation to a loading dock area. Once the low-speed maneuvering mode is selected, a control unit controls at least one of engine speed and engine torque to indirectly effect clutch slippage, which results in improved vehicle speed control at low-speed operations.

Abstract: A clutch assembly includes a reaction surface that provides several disengagement surfaces that cause axial movement of a front plate to reduce torque transmission at rotational speeds above an engagement speed. The disengagement surfaces reduce torque to break torque lock at rotational speeds corresponding to desired gear changes. The clutch assembly is controlled to tailor the relationship between clutch torque and engine speed to current vehicle operating conditions to provide consistent vehicle performance over different operating conditions.