Centrifugal clutch mechanisms, and transmissions and lawnmowers having centrifugal clutch mechanisms are provided. A centrifugal clutch mechanism includes a clutch bell comprising an annular wall and a circular ring extending away from the annular wall to define an internal cavity, wherein the circular ring comprises an inward facing surface defining a drive surface. The centrifugal clutch mechanism also includes a plurality of centrifugal weights disposed in the internal cavity and an inward biasing element engaged with the centrifugal weights. The inward biasing element biases the centrifugal weights towards a disengaged position in which the centrifugal weights do not interface with drive surface, and upon application of a sufficient centrifugal force, the centrifugal weights are configured to transition to an engaged position in which the centrifugal weights interface with the drive surface.

Centrifugal clutch mechanisms, and transmissions and lawnmowers having centrifugal clutch mechanisms are provided. A centrifugal clutch mechanism includes a clutch bell comprising an annular wall and a circular ring extending away from the annular wall to define an internal cavity, wherein the circular ring comprises an inward facing surface defining a drive surface. The centrifugal clutch mechanism also includes a plurality of centrifugal weights disposed in the internal cavity and an inward biasing element engaged with the centrifugal weights. The inward biasing element biases the centrifugal weights towards a disengaged position in which the centrifugal weights do not interface with drive surface, and upon application of a sufficient centrifugal force, the centrifugal weights are configured to transition to an engaged position in which the centrifugal weights interface with the drive surface.

During movement of a mass of a centrifugal clutch a radially inner position to a radially outer position and a resulting increase in torque transmitted from an input gear to an output shaft, a power transmission apparatus includes a first torque region where the apparatus restricts operation of a pressing assist cam and a second torque region where the apparatus allows operation of the pressing assist cam.

During movement of a mass of a centrifugal clutch a radially inner position to a radially outer position and a resulting increase in torque transmitted from an input gear to an output shaft, a power transmission apparatus includes a first torque region where the apparatus restricts operation of a pressing assist cam and a second torque region where the apparatus allows operation of the pressing assist cam.

The present invention discloses an electromagnetic clutch of a brushless control-by-wire centrifugal ball arm engagement device, which comprises a brushless electromagnet, a thrust pressing disc, a driven inner-spline hub, a control-by-wire drive disc, a centrifugal ball arm hollow disc, centrifugal ball arm pins, centrifugal ball arms, centrifugal balls, a magnetic conductive force transmitting disk, a drive shaft; once the brushless electromagnet is energized, the centrifugal ball arms and the centrifugal balls each make a circular motion around the centrifugal ball arm pin outwardly along the smooth surface of the thrust pressing disc by the action of centrifugal force produced by them when rotating with high speed. The component of the centrifugal force in the direction of the central axis of the centrifugal ball arm hollow disc drives the thrust pressing disc to compress the outer-spline-groove steel sheets and the inner-spline-groove friction discs with each other, which makes the clutch engaged. The clutch is engaged smoothly with no impact, which is suitable for high-speed rotation and transmitting large torque.

A clutch assembly includes an output shaft extending along an axis and output teeth. A movable component is disposed adjacent to the output component. The movable component includes drive teeth and an annular engagement weight track including a groove circumscribing the axis. The movable component is movable between an engaged position, wherein the drive teeth are drivingly engaged with the output teeth, and a disengaged position, wherein the drive teeth are not engaged with the output teeth. An input component is disposed adjacent to the movable component. The input component includes engagement weight pockets. Spherical engagement weights are disposed in each engagement weight pocket. The groove has a generally uniform radial cross section across its circumference.

A one way clutch comprises an outer race including a radially outer first annular part to which rotation is input from outside and a radially inner second annular part capable of rotating when receiving rotation from the first annular part, an inner race provided radially inside the outer race and rotatable relative to the outer race, a plurality of torque transmission members provided between the outer race and the inner race to transmit torque between the outer race and the inner race, and a coupling mechanism that couples the first annular part and the second annular part together to make them integrally rotatable when the speed of rotation input from outside is lower than a specific speed and decouples them when the speed of rotation exceeds the specific speed.

A one way clutch comprises an outer race including a radially outer first annular part to which rotation is input from outside and a radially inner second annular part capable of rotating when receiving rotation from the first annular part, an inner race provided radially inside the outer race and rotatable relative to the outer race, a plurality of torque transmission members provided between the outer race and the inner race to transmit torque between the outer race and the inner race, and a coupling mechanism that couples the first annular part and the second annular part together to make them integrally rotatable when the speed of rotation input from outside is lower than a specific speed and decouples them when the speed of rotation exceeds the specific speed.

A friction clutch for a drivetrain of a motor vehicle includes an engine-side input part, a transmission-side output part, friction elements, an engine-side actuating device, and a transmission-side actuating device. The engine-side input part is disposed rotatably around an axis of rotation. The friction elements are arranged for frictionally engaging the engine-side input part to the transmission-side output part. The engine-side actuating device is arranged between the engine-side input part and the friction elements. The transmission-side actuating device is arranged between the transmission-side output part and the friction elements. At least one of the engine-side actuating device or the transmission-side actuating device is a centrifugal force controlled actuating device arranged to clamp the friction elements against one another.

A friction clutch for a drivetrain of a motor vehicle includes an engine-side input part, a transmission-side output part, friction elements, an engine-side actuating device, and a transmission-side actuating device. The engine-side input part is disposed rotatably around an axis of rotation. The friction elements are arranged for frictionally engaging the engine-side input part to the transmission-side output part. The engine-side actuating device is arranged between the engine-side input part and the friction elements. The transmission-side actuating device is arranged between the transmission-side output part and the friction elements. At least one of the engine-side actuating device or the transmission-side actuating device is a centrifugal force controlled actuating device arranged to clamp the friction elements against one another.