Abstract: A stall detection system for mower blade clutch engagement determines if there is a stall condition by sensing one or more operating conditions such as engine deceleration or blade spindle rotation. If a stall condition is detected, a microcontroller shuts off actuating current to the electric clutch coil and automatically disengages or discontinues engagement of the clutch. The microcontroller may also provide a signal to inform the operator of the stall condition, and prevent repeated activation of the clutch until the stall condition is corrected.

Abstract: A stall detection system for mower blade clutch engagement determines if there is a stall condition by sensing one or more operating conditions such as engine deceleration or blade spindle rotation. If a stall condition is detected, a microcontroller shuts off actuating current to the electric clutch coil and automatically disengages or discontinues engagement of the clutch. The microcontroller may also provide a signal to inform the operator of the stall condition, and prevent repeated activation of the clutch until the stall condition is corrected.

Abstract: A variable speed friction drive apparatus for a lawn mower includes a pair of drive cones supported by a frame for rotational movement about a common first axis, and a pair of drums supported by carriages for rotation about axes transverse to the lengths of the carriages. Each carriage is supported on the frame for movement between a neutral position in which the associated drum is disengaged from either of the cones and a plurality of driving positions in which the drum engages either of the cones. A universal joint connects the rear end of each carriage to the frame for universal pivotal movement about the joint, and both ends of each carriage are independently biased toward the neutral position.