Patent ID: 7249450

Claim:
A lawn mower comprising: a power source for rotatably driving an output shaft; a housing having an interior space having a generally spiral-shaped portion; a cutting blade disposed in the interior space of the housing and connected to the output shaft for rotation therewith to cut grass and coacting with the spiral-shaped portion of the interior space to generate a swirling air flow that causes the cut grass to swirl within the interior space; a grass discharge passage having an inlet end portion that opens into the interior space of the housing for receiving grass cut by the cutting blade and swirling within the interior space of the housing and a discharge end portion for discharging the cut grass; a grass receptacle detachably attached to the discharge end portion of the discharge passage; and a pivotal shutter disposed at the inlet end portion of the grass discharge passage and pivotal about a generally vertical axis for opening and closing the grass discharge passage, the pivotal shutter being pivotable between at least a first fully-closed position in which the pivotal shutter fully closes the grass discharge passage to permit the lawn mower to undergo a mulching operation for cutting grass cut by the cutting blade more finely within the housing and discharging the cut grass downward of the housing, and a second fully-opened position in which the pivotal shutter projects into and fully opens the grass discharge passage to permit the lawn mower to undergo a bagging operation for receiving in the grass receptacle grass cut by the cutting blade; wherein the pivotal shutter does not project into the interior space of the housing during pivotal movement thereof between the first and second positions, and wherein the grass receptacle is detachable from and attachable to the discharge end portion of the grass discharge passage independently of pivotal movement of the pivotal shutter between the first position and the second position.