US Patent 9309638 Snowthrower impeller assembly with rigid cutting implement

An impeller assembly for a snowthrower includes a driven shaft configured to rotate about an axis, a flexible impeller paddle coupled to the driven shaft for rotation about the axis, and a rigid cutting implement coupled to the driven shaft for rotation about the axis. The flexible impeller paddle is configured to clear snow from a surface to be cleared. The flexible impeller paddle extends radially from the axis to a paddle radial distance. The rigid cutting implement is configured to break up snow or ice on the surface to be cleared. The rigid cutting implement extends radially from the axis to a cutting implement radial distance less than the paddle radial distance.