Abstract: A walk-behind, self-propelled lawn mower having a variable speed drive transmission responsive to operator-applied forces. The transmission includes an input gear operatively connected to the engine for constant rotation during operation, an intermediate gear meshed with the input gear, and a driving bevel gear meshed with a drive shaft bevel gear. A face of the driving bevel gear is biased away from a face of the intermediate gear. A clutching surface is interposed between the gear faces for coupling the intermediate gear and the driving bevel gear in driving engagement. An actuator lever is controllably connected to the intermediate gear and can be adjusted to vary the sensitivity of the drive transmission to operator-applied forces.

Abstract: A walk-behind, self-propelled lawn mower having a variable speed drive transmission responsive to operator applied forces. The drive transmission is mounted on a frame and comprises gearing operatively connected to an engine and a drive shaft for transmitting forces from the engine to the shaft. A clutching structure including a frictional coupling is coactable with an element of the gearing selectively to provide force transmission to the drive shaft. An actuator structure is controllably connected to the clutching structure and responsive to operator applied forces for controlling the speed at which the lawn mower traverses along a ground surface and to vary the speed proportionally to operator applied forces. The lawn mower also includes a handle pivotally connected to the frame and operatively connected to the actuator structure. The handle is adapted to pivot in response to the operator applied forces.