Patent ID: 8277528

Claim:
A dust removal system for a riding lawn mower comprising an engine disposed within an engine compartment partitioned by a separating wall, a speed change device disposed outside of the engine compartment, and a universal coupling inserted through an opening provided in the separating wall in order to connect an output shaft of the engine with an input shaft of the speed change device; the dust removal system comprising: a perforated board which rotates integrally with the output shaft around the axis of the output shaft in order to inhibit grass cuttings from flowing into the engine compartment through the opening, wherein the perforated board comprises a centrally located insertion hole defined by an inner peripheral edge of the perforated board, and the insertion hole comprises a diameter sufficiently large to avoid contact interference between the inner peripheral edge of the perforated board and an outer periphery of the universal coupling, the inner peripheral edge of the perforated board and the outer periphery of the universal coupling defining a space therebetween; and a seal unit substantially sealing the space between the outer periphery of the universal coupling and the inner peripheral edge of the perforated board.