| 摘要 |
A vegetation cutting implement includes a rotatable support head which mounts a hub having a plurality of cutter elements comprising self-supporting struts. Each strut is more than 50% non-metallic material (typically more than 90% plastic or rubber), and the hub is readily replaceable in the vegetation cutting implement merely by detaching a fastener. Typically the cutter elements are integral with the hub, although a number of radially extending openings may be provided through which individually replaceable cutter elements pass. The self-supporting struts each preferably comprise a beam-like structure with a first axis which is the strongest axis and has a highest moment of inertia and a second, weaker axis, and the head is rotated so that the first axis of the beam-like structure of each strut is positively maintained and moves in a predetermined cutting plane which is generally transverse to a portion of vegetation to be cut. Because of the self-supporting nature of the struts, and their association with the hub, they are inherently positively maintained in the appropriate position for cutting.
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