| 摘要 |
A compact lawn aerator comprises a rigid frame having a hitch for releasably fastening tire frame to the back of a self-propelled mower. An elongated axle is secured to the under side of the frame and a set of aerator wheels are rotatably mounted at spaced intervals along the axle. Each of the aerator wheels has a generally disk-shaped hub from the periphery of which four spikes radiate. Each spike initially projects from the hub along a radius but curves along its length in the direction of rotation of the wheel. The spikes are tapered to a sharpened point and their curve is determined so that, as the wheel rotates, the ends of the spikes pierce the soil at substantially right angles and the shank of the spikes slip into the ground progressively through the pierce point. This greatly reduces the force needed to drive the spikes into the ground, thus reducing the weight and size of the device. Further, as the spikes continue to rotate out of the soil, their curved shape functions as a cupped spade that tears and pulls a soil pug from the ground, leaving a loosely packed hole through which air can freely migrate into surrounding soil. The downward force imparted by the pulling out of the soil plug helps drive the successive plug into the ground, further significantly reducing the required weight of the device. In an alternate embodiment, independently suspended and independently castered single wheel aerator assemblies are hitched at spaced intervals along the back of a mower.
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