Centrifugal clutch mechanisms

A centrifugal clutch mechanism in selective mechanical communication between a first gear assembly and a second gear assembly to transfers energy from the first stage assembly to the second stage assembly, the centrifugal clutch mechanism comprising:

• 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;
• a plurality of centrifugal weights disposed in the internal cavity, the one or more centrifugal weights being linearly slidable along a radial direction perpendicular to a center axis of the centrifugal clutch mechanism;
• and
• an inward biasing element engaged with the centrifugal weights, wherein the inward biasing element biases the centrifugal weights towards a disengaged position in which the centrifugal weights do not interface with the drive surface, and wherein upon application of a sufficient centrifugal force, the centrifugal weights are configured to transition along the radial direction to an engaged position in which the centrifugal weights interface with the drive surface,
• wherein at least one of the plurality of centrifugal weights comprises an axial projection extending away from the clutch bell, and
• wherein the axial projection is complementary to and received within a linear guide slot defined within the first gear assembly to guide sliding of the at least one centrifugal weight along the linear guide slot in the radial direction.

A lawnmower comprising:

• a motor;
• a first stage gear operably coupled to the motor;
• a second stage gear;
• a plurality of wheels operably coupled to the second stage gear via an axle;
• and
• a centrifugal clutch mechanism that transfers energy from the first stage gear to the second stage gear, the centrifugal clutch mechanism comprising:
• a clutch bell comprising an annular wall and a circular ring extending away from the annular wall towards the first stage gear to define an internal cavity, wherein the circular ring comprises an inward facing surface defining a drive surface;
• and
• one or more centrifugal weights disposed in the internal cavity between the annular wall and the first stage gear, wherein the one or more centrifugal weights are slidingly engaged with the first stage gear, the one or more centrifugal weights being linearly slidable along a radial direction perpendicular to a center axis of the centrifugal clutch mechanism;
• wherein the second stage gear is rotatably coupled to the clutch bell;
• and
• wherein rotation of the first stage gear by the motor causes the one or more centrifugal weights to transition along the radial direction from a disengaged position in which the one or more centrifugal weights do not interface with the drive surface to an engaged position in which the one or more centrifugal weights interface with the drive surface to transfer rotational energy from the first stage gear to the second stage gear.