Rotary lawn mower mulching deck

Abstract

The invention provides a rotary lawn mower with an improved mulching deck. The rotary lawn mower comprises a plurality of sets of cutting blades. Each of the blade sets includes a lower, leading blade and an upper, trailing blade. The lower blade has a leading cutting edge and an upwardly angled trailing edge. The upper trailing blade extends at an angle relative to the leading blade and has a leading cutting edge for cutting clippings deflected upwardly by the upwardly angled trailing edge of the leading blade. The lawn mower further comprises a mulching deck including a plastic, dent-resistant, rust-proof insert which is positioned in the deck. The insert provides correct air flow for mulching and a sound barrier for reduced noise. The insert defines a plurality of recesses. A blade set is mounted for rotation about an axis of each recess. The insert includes an integral, arcuate baffle extending downwardly adjacent the periphery of one of the recesses impeding air flow from the one recess to an adjacent recess. The insert also includes an integral projection in one of the left and right recesses such that the recess has a decreased height in the area of the projection. The projection prevents downward flow of air that would otherwise result from converging air from two adjacent blade sets. The lawn mower further comprises a front deflector removably mounted on the front portion of the deck side wall to allow venting of air but not discharge of clippings from the front of the deck.